Fourmilog: None Dare Call It Reason

Reading List: Liberators

Wednesday, November 26, 2014 23:37

Rawles, James Wesley. Liberators. New York: Dutton, 2014. ISBN 978-0-525-95391-3.
This novel is the fifth in the series which began with Patriots (December 2008), then continued with Survivors (January 2012), Founders (October 2012), and Expatriates (October 2013), These books are not a conventional multi-volume narrative, in that all describe events in the lives of their characters in roughly the same time period surrounding “the Crunch”—a grid down societal collapse due to a debt crisis and hyperinflation. Taking place at the same time, you can read these books in any order, but if you haven't read the earlier novels you'll miss much of the back-story of the characters who appear here, which informs the parts they play in this episode.

Here the story cuts back and forth between the United States, where Megan LaCroix and her sister Malorie live on a farm in West Virginia with Megan's two boys, and Joshua Kim works in security at the National Security Agency where Megan is an analyst. When the Crunch hits, Joshua and the LaCroix sisters decide to team up to bug out to Joshua's childhood friend's place in Kentucky, where survival from the urban Golden Horde may be better assured. They confront the realities of a collapsing society, where the rule of law is supplanted by extractive tyrannies, and are forced to over-winter in a wilderness, living by their wits and modest preparations.

In Western Canada, the immediate impact of the Crunch was less severe because electrical power, largely hydroelectric, remained on. At the McGregor Ranch, in inland British Columbia (a harsh, northern continental climate nothing like that of Vancouver), the family and those who have taken refuge with them ride out the initial crisis only to be confronted with an occupation of Canada by a nominally United Nations force called UNPROFOR, which is effectively a French colonial force which, in alliance with effete urban eastern and francophone Canada, seeks to put down the fractious westerners and control the resource-rich land they inhabit.

This leads to an asymmetrical war of resistance, aided by the fact that when earlier faced with draconian gun registration and prohibition laws imposed by easterners, a large number of weapons in the west simply vanished, only to reappear when they were needed most. As was demonstrated in Vietnam and Algeria, French occupation forces can be tenacious and brutal, but are ultimately no match for an indigenous insurgency with the support of the local populace. A series of bold strikes against UNPROFOR assets eventually turns the tide.

But just when Canada seems ready to follow the U.S. out of the grip of tyranny, an emboldened China, already on the march in Africa, makes a move to seize western Canada's abundant natural resources. Under the cover of a UN resolution, a massive Chinese force, with armour and air support, occupies the western provinces. This is an adversary of an entirely different order than the French, and will require the resistance, supported by allies from the liberation struggle in the U.S., to audacious and heroic exploits, including one of the greatest acts of monkey-wrenching ever described in a thriller.

As this story has developed over the five novels, the author has matured into a first-rate thriller novelist. There is still plenty of information on gear, tactics, intelligence operations, and security, but the characters are interesting, well-developed, and the action scenes both plausible and exciting. In the present book, we encounter many characters we've met in previous volumes, with their paths crossing as events unfold. There is no triumphalism or glossing over the realities of insurgent warfare against a tyrannical occupying force. There is a great deal of misery and hardship, and sometimes tragedy can result when you've taken every precaution, made no mistake, but simply run out of luck.

Taken together, these five novels are an epic saga of survival in hard and brutal times, painted on a global canvas. Reading them, you will not only be inspired that you and your loved ones can survive such a breakdown in the current economic and social order, but you will also learn a great deal of the details of how to do so. This is not a survival manual, but attentive readers will find many things to research further for their own preparations for an uncertain future. An excellent place to begin that research is the author's own Web site, whose massive archives you can spend months exploring.


Reading List: Undercover Mormon

Sunday, November 23, 2014 15:56

Metzger, Th. Undercover Mormon. New York: Roadswell Editions, 2013.
The author, whose spiritual journey had earlier led him to dabble with becoming a Mennonite, goes weekly to an acupuncturist named Rudy Kilowatt who believes in the power of crystals, attends neo-pagan fertility rituals in a friend's suburban back yard, had been oddly fascinated by Mormonism ever since, as a teenager, he attended the spectacular annual Mormon pageant at Hill Cumorah, near his home in upstate New York.

He returned again and again for the spectacle of the pageant, and based upon his limited knowledge of Mormon doctrine, found himself admiring how the religion seemed to have it all: “All religion is either sword and sorcery or science fiction. The reason Mormonism is growing so fast is that you guys have both, and don't apologize for either.” He decides to pursue this Mormon thing further, armouring himself in white shirt, conservative tie, and black pants, and heading off to the nearest congregation for the Sunday service.

Approached by missionaries who spot him as a newcomer, he masters his anxiety (bolstered by the knowledge he has a couple of Xanax pills in his pocket), gives a false name, and indicates he's interested in learning more about the faith. Before long he's attending Sunday school, reading tracts, and spinning into the Mormon orbit, with increasing suggestions that he might convert.

All of this is described in a detached, ironic manner, in which the reader (and perhaps the author) can't decide how seriously to take it all. Metzger carries magic talismans to protect himself against the fearful “Mormo”, describes his anxiety to his psychoanalyst, who prescribes the pharmaceutical version of magic bones. He struggles with paranoia about his deception being found out and agonises over the consequences. He consults a friend who, “For a while he was an old-order Quaker, then a Sufi, then a retro-neo-pagan. Now he's a Unitarian-Universalist professor of history.”

The narrative is written in the tediously quaint “new journalism” style where it's as much about the author as the subject. This works poorly here because the author isn't very interesting. He comes across as so neurotic and self-absorbed as to make Woody Allen seem like Clint Eastwood. His “discoveries” about the content of LDS scripture could have been made just as easily by reading the original documents on the LDS Web site, and his exploration of the history of Joseph Smith and the early days of Mormonism in New York could have been accomplished by consulting Wikipedia. His antics, such as burying chicken bones around the obelisk of Moroni on Hill Cumorah and digging up earth from the grave of Luman Walter to spread it in the sacred grove, push irony past the point of parody—does anybody believe the author took such things seriously (and if he did, why should anybody care what he thinks about anything)?

The book does not mock Mormonism, and treats the individuals he encounters on his journey more or less respectfully (with just that little [and utterly unjustified] “I'm better than you” that the hip intellectual has for earnest, clean-cut, industrious people who are “as white as angel food cake, and almost as spongy.”) But you'll learn nothing about the history and doctrine of the religion here that you won't find elsewhere without all the baggage of the author's tiresome “adventures”.


Reading List: Command and Control

Thursday, November 6, 2014 23:49

Schlosser, Eric. Command and Control. New York: Penguin, 2013. ISBN 978-0-14-312578-5.
On the evening of September 18th, 1980 two U.S. Air Force airmen, members of a Propellant Transfer System (PTS) team, entered a Titan II missile silo near Damascus, Arkansas to perform a routine maintenance procedure. Earlier in the day they had been called to the site because a warning signal had indicated that pressure in the missile's second stage oxidiser tank was low. This was not unusual, especially for a missile which had recently been refuelled, as this one had, and the procedure of adding nitrogen gas to the tank to bring the pressure up to specification was considered straightforward. That is, if you consider any work involving a Titan II “routine” or “straightforward”. The missile, in an underground silo, protected by a door weighing more than 65 tonnes and able to withstand the 300 psi overpressure of a nearby nuclear detonation, stood more than 31 metres high and contained 143 tonnes of highly toxic fuel and oxidiser which, in addition to being poisonous to humans in small concentrations, were hypergolic: they burst into flames upon contact with one another, with no need of a source of ignition. Sitting atop this volatile fuel was a W-53 nuclear warhead with a yield of 9 megatons and high explosives in the fission primary which were not, as more modern nuclear weapons, insensitive to shock and fire. While it was unlikely in the extreme that detonation of these explosives due to an accident would result in a nuclear explosion, they could disperse the radioactive material in the bomb over the local area, requiring a massive clean-up effort.

The PTS team worked on the missile wearing what amounted to space suits with their own bottled air supply. One member was an experienced technician while the other was a 19-year old rookie receiving on the job training. Early in the procedure, the team was to remove the pressure cap from the side of the missile. While the lead technician was turning the cap with a socket wrench, the socket fell off the wrench and down the silo alongside the missile. The socket struck the thrust mount supporting the missile, bounced back upward, and struck the side of the missile's first stage fuel tank. Fuel began to spout outward as if from a garden hose. The trainee remarked, “This is not good.”

Back in the control centre, separated from the silo by massive blast doors, the two man launch team who had been following the servicing operation, saw their status panels light up like a Christmas tree decorated by somebody inordinately fond of the colour red. The warnings were contradictory and clearly not all correct. Had there indeed been both fuel and oxidiser leaks, as indicated, there would already have been an earth-shattering kaboom from the silo, and yet that had not happened. The technicians knew they had to evacuate the silo as soon as possible, but their evacuation route was blocked by dense fuel vapour.

The Air Force handles everything related to missiles by the book, but the book was silent about procedures for a situation like this, with massive quantities of toxic fuel pouring into the silo. Further, communication between the technicians and the control centre were poor, so it wasn't clear at first just what had happened. Before long, the commander of the missile wing, headquarters of the Strategic Air Command (SAC) in Omaha, and the missile's manufacturer, Martin Marietta, were in conference trying to decide how to proceed. The greatest risks were an electrical spark or other source of ignition setting the fuel on fire or, even greater, of the missile collapsing in the silo. With tonnes of fuel pouring from the fuel tank and no vent at its top, pressure in the tank would continue to fall. Eventually, it would be below atmospheric pressure, and would be crushed, likely leading the missile to crumple under the weight of the intact and fully loaded first stage oxidiser and second stage tanks. These tanks would then likely be breached, leading to an explosion. No Titan II had ever exploded in a closed silo, so there was no experience as to what the consequences of this might be.

As the night proceeded, all of the Carter era military malaise became evident. The Air Force lied to local law enforcement and media about what was happening, couldn't communicate with first responders, failed to send an evacuation helicopter for a gravely injured person because an irrelevant piece of equipment wasn't available, and could not come to a decision about how to respond as the situation deteriorated. Also on display was the heroism of individuals, in the Air Force and outside, who took matters into their own hands on the spot, rescued people, monitored the situation, evacuated nearby farms in the path of toxic clouds, and improvised as events required.

Among all of this, nothing whatsoever had been done about the situation of the missile. Events inevitably took their course. In the early morning hours of September 19th, the missile collapsed, releasing all of its propellants, which exploded. The 65 tonne silo door was thrown 200 metres, shearing trees in its path. The nuclear warhead was thrown two hundred metres in another direction, coming to rest in a ditch. Its explosives did not detonate, and no radiation was released.

While there were plenty of reasons to worry about nuclear weapons during the Cold War, most people's concerns were about a conflict escalating to the deliberate use of nuclear weapons or the possibility of an accidental war. Among the general public there was little concern about the tens of thousands of nuclear weapons in depots, aboard aircraft, atop missiles, or on board submarines—certainly every precaution had been taken by the brilliant people at the weapons labs to make them safe and reliable, right?

Well, that was often the view among “defence intellectuals” until they were briefed in on the highly secret details of weapons design and the command and control procedures in place to govern their use in wartime. As documented in this book, which uses the Damascus accident as a backdrop (a ballistic missile explodes in rural Arkansas, sending its warhead through the air, because somebody dropped a socket wrench), the reality was far from reassuring, and it took decades, often against obstructionism and foot-dragging from the Pentagon, to remedy serious risks in the nuclear stockpile.

In the early days of the U.S. nuclear stockpile, it was assumed that nuclear weapons were the last resort in a wartime situation. Nuclear weapons were kept under the civilian custodianship of the Atomic Energy Commission (AEC), and would only be released to the military services by a direct order from the President of the United States. Further, the nuclear cores (“pits”) of weapons were stored separately from the rest of the weapon assembly, and would only be inserted in the weapon, in the case of bombers, in the air, after the order to deliver the weapon was received. (This procedure had been used even for the two bombs dropped on Japan.) These safeguards meant that the probability of an accidental nuclear explosion was essentially nil in peacetime, although the risk did exist of radioactive contamination if a pit were dispersed due to fire or explosion.

As the 1950s progressed, and fears of a Soviet sneak attack grew, pressure grew to shift the custodianship of nuclear weapons to the military. The development of nuclear tactical and air defence weapons, some of which were to be forward deployed outside the United States, added weight to this argument. If radar detected a wave of Soviet bombers heading for the United States, how practical would it be to contact the President, get him to sign off on transferring the anti-aircraft warheads to the Army and Air Force, have the AEC deliver them to the military bases, install them on the missiles, and prepare the missiles for launch? The missile age only compounded this situation. Now the risk existed for a “decapitation” attack which could take out the senior political and military leadership, leaving nobody with the authority to retaliate.

The result of all this was a gradual devolution of control over nuclear weapons from civilian to military commands, with fully-assembled nuclear weapons loaded on aircraft, sitting at the ends of runways in the United States and Europe, ready to take off on a few minutes' notice. As tensions continued to increase, B-52s, armed with hydrogen bombs, were on continuous “airborne alert”, ready at any time to head toward their targets.

The weapons carried by these aircraft, however, had not been designed for missions like this. They used high explosives which could be detonated by heat or shock, often contained few interlocks to prevent a stray electrical signal from triggering a detonation, were not “one point safe” (guaranteed that detonation of one segment of the high explosives could not cause a nuclear yield), and did not contain locks (“permissive action links”) to prevent unauthorised use of a weapon. Through much of the height of the Cold War, it was possible for a rogue B-52 or tactical fighter/bomber crew to drop a weapon which might start World War III; the only protection against this was rigid psychological screening and the enemy's air defence systems.

The resistance to introducing such safety measures stemmed from budget and schedule pressures, but also from what was called the “always/never” conflict. A nuclear weapon should always detonate when sent on a wartime mission. But it should never detonate under any other circumstances, including an airplane crash, technical malfunction, maintenance error, or through the deliberate acts of an insane or disloyal individual or group. These imperatives inevitably conflict with one another. The more safeguards you design into a weapon to avoid an unauthorised detonation, the greater the probability one of them may fail, rendering the weapon inert. SAC commanders and air crews were not enthusiastic about the prospect of risking their lives running the gauntlet of enemy air defences only to arrive over their target and drop a dud.

As documented here, it was only after the end of Cold War, as nuclear weapon stockpiles were drawn down, that the more dangerous weapons were retired and command and control procedures put into place which seem (to the extent outsiders can assess such highly classified matters) to provide a reasonable balance between protection against a catastrophic accident or unauthorised launch and a reliable deterrent.

Nuclear command and control extends far beyond the design of weapons. The author also discusses in detail the development of war plans, how civilian and military authorities interact in implementing them, how emergency war orders are delivered, authenticated, and executed, and how this entire system must be designed not only to be robust against errors when intact and operating as intended, but in the aftermath of an attack.

This is a serious scholarly work and, at 632 pages, a long one. There are 94 pages of end notes, many of which expand substantially upon items in the main text. A Kindle edition is available.


Floating Point Benchmark: Rust Language Added

Sunday, October 26, 2014 00:31

I have posted an update to my trigonometry-intense floating point benchmark which adds Rust to the list of languages in which the benchmark is implemented. A new release of the benchmark collection including Rust is now available for downloading.

Rust is a systems programming language currently under development. It attempts to provide performance comparable to low-level programming languages such as C and C++ while avoiding common causes of crashes and security problems such as subscript and pointer errors, dangling pointers, memory leaks, and multi-thread race conditions. It is a compiled language with extensive compile-time checking which detects many errors which cause run-time errors in other languages, and has a reference-counted memory management architecture which avoids the overhead of garbage collection and provides critical section locking in multi-thread programs.

As a language actively under development, Rust is a moving target and any program developed for it may require modification as the language and run-time libraries evolve. This program was developed on version 0.13.0, and I encountered no problems with the language or libraries. Rust supports multiple programming paradigms: I chose to implement this program in a functional style with no mutable variables.

The relative performance of the various language implementations (with C taken as 1) is as follows. All language implementations of the benchmark listed below produced identical results to the last (11th) decimal place.

Language Relative
C 1 GCC 3.2.3 -O3, Linux
Visual Basic .NET 0.866 All optimisations, Windows XP
FORTRAN 1.008 GNU Fortran (g77) 3.2.3 -O3, Linux
Pascal 1.027
Free Pascal 2.2.0 -O3, Linux
GNU Pascal 2.1 (GCC 2.95.2) -O3, Linux
Rust 1.077 Rust 0.13.0, --release, Linux
Java 1.121 Sun JDK 1.5.0_04-b05, Linux
Visual Basic 6 1.132 All optimisations, Windows XP
Haskell 1.223 GHC 7.4.1-O2 -funbox-strict-fields, Linux
Ada 1.401 GNAT/GCC 3.4.4 -O3, Linux
Go 1.481 Go version go1.1.1 linux/amd64, Linux
Simula 2.099 GNU Cim 5.1, GCC 4.8.1 -O2, Linux
Lua 2.515
LuaJIT 2.0.3, Linux
Lua 5.2.3, Linux
Python 2.633
PyPy 2.2.1 (Python 2.7.3), Linux
Python 2.7.6, Linux
Erlang 3.663
Erlang/OTP 17, emulator 6.0, HiPE [native, {hipe, [o3]}]
Byte code (BEAM), Linux
ALGOL 60 3.951 MARST 2.7, GCC 4.8.1 -O3, Linux
Lisp 7.41
GNU Common Lisp 2.6.7, Compiled, Linux
GNU Common Lisp 2.6.7, Interpreted
Smalltalk 7.59 GNU Smalltalk 2.3.5, Linux
Forth 9.92 Gforth 0.7.0, Linux
COBOL 12.5
Micro Focus Visual COBOL 2010, Windows 7
Fixed decimal instead of computational-2
Algol 68 15.2 Algol 68 Genie 2.4.1 -O3, Linux
Perl 23.6 Perl v5.8.0, Linux
Ruby 26.1 Ruby 1.8.3, Linux
JavaScript 27.6
Opera 8.0, Linux
Internet Explorer 6.0.2900, Windows XP
Mozilla Firefox 1.0.6, Linux
QBasic 148.3 MS-DOS QBasic 1.1, Windows XP Console

This is a very impressive performance for a language whose specification continues to be refined and with a compiler under active development. There are few applications where an 8% speed penalty compared to C/C++ will make much of a difference (note, of course, that many systems programming applications do things very different that this floating-point intensive benchmark, and that relative performance measured by this program may not be indicative of what you'll experience on very different tasks such as text processing, management of large data structures, or parallel computation).


Reading List: The Great Influenza

Saturday, October 18, 2014 21:34

Barry, John M. The Great Influenza. New York: Penguin, [2004] 2005. ISBN 978-0-14-303649-4.
In the year 1800, the practice of medicine had changed little from that in antiquity. The rapid progress in other sciences in the 18th century had had little impact on medicine, which one historian called “the withered arm of science”. This began to change as the 19th century progressed. Researchers, mostly in Europe and especially in Germany, began to lay the foundations for a scientific approach to medicine and public health, understanding the causes of disease and searching for means of prevention and cure. The invention of new instruments for medical examination, anesthesia, and antiseptic procedures began to transform the practice of medicine and surgery.

All of these advances were slow to arrive in the United States. As late as 1900 only one medical school in the U.S. required applicants to have a college degree, and only 20% of schools required a high school diploma. More than a hundred U.S. medical schools accepted any applicant who could pay, and many graduated doctors who had never seen a patient or done any laboratory work in science. In the 1870s, only 10% of the professors at Harvard's medical school had a Ph.D.

In 1873, Johns Hopkins died, leaving his estate of US$ 3.5 million to found a university and hospital. The trustees embarked on an ambitious plan to build a medical school to be the peer of those in Germany, and began to aggressively recruit European professors and Americans who had studied in Europe to build a world class institution. By the outbreak of World War I in Europe, American medical research and education, still concentrated in just a few centres of excellence, had reached the standard set by Germany. It was about to face its greatest challenge.

With the entry of the United States into World War I in April of 1917, millions of young men conscripted for service were packed into overcrowded camps for training and preparation for transport to Europe. These camps, thrown together on short notice, often had only rudimentary sanitation and shelter, with many troops living in tent cities. Large number of doctors and especially nurses were recruited into the Army, and by the start of 1918 many were already serving in France. Doctors remaining in private practice in the U.S. were often older men, trained before the revolution in medical education and ignorant of modern knowledge of diseases and the means of treating them.

In all American wars before World War I, more men died from disease than combat. In the Civil War, two men died from disease for every death on the battlefield. Army Surgeon General William Gorgas vowed that this would not be the case in the current conflict. He was acutely aware that the overcrowded camps, frequent transfers of soldiers among far-flung bases, crowded and unsanitary troop transport ships, and unspeakable conditions in the trenches were a tinderbox just waiting for the spark of an infectious disease to ignite it. But the demand for new troops for the front in France caused his cautions to be overruled, and still more men were packed into the camps.

Early in 1918, a doctor in rural Haskell County, Kansas began to treat patients with a disease he diagnosed as influenza. But this was nothing like the seasonal influenza with which he was familiar. In typical outbreaks of influenza, the people at greatest risk are the very young (whose immune systems have not been previously exposed to the virus) and the very old, who lack the physical resilience to withstand the assault by the disease. Most deaths are among these groups, leading to a “bathtub curve” of mortality. This outbreak was different: the young and elderly were largely spared, while those in the prime of life were struck down, with many dying quickly of symptoms which resembled pneumonia. Slowly the outbreak receded, and by mid-March things were returning to normal. (The location and mechanism where the disease originated remain controversial to this day and we may never know for sure. After weighing competing theories, the author believes the Kansas origin most likely, but other origins have their proponents.)

That would have been the end of it, had not soldiers from Camp Funston, the second largest Army camp in the U.S., with 56,000 troops, visited their families in Haskell County while on leave. They returned to camp carrying the disease. The spark had landed in the tinderbox. The disease spread outward as troop trains travelled between camps. Often a train would leave carrying healthy troops (infected but not yet symptomatic) and arrive with up to half the company sick and highly infectious to those at the destination. Before long the disease arrived via troop ships at camps and at the front in France.

This was just the first wave. The spring influenza was unusual in the age group it hit most severely, but was not particularly more deadly than typical annual outbreaks. Then in the fall a new form of the disease returned in a much more virulent form. It is theorised that under the chaotic conditions of wartime a mutant form of the virus had emerged and rapidly spread among the troops and then passed into the civilian population. The outbreak rapidly spread around the globe, and few regions escaped. It was particularly devastating to aboriginal populations in remote regions like the Arctic and Pacific islands who had not developed any immunity to influenza.

The pathogen in the second wave could kill directly within a day by destroying the lining of the lung and effectively suffocating the patient. The disease was so virulent and aggressive that some medical researchers doubted it was influenza at all and suspected some new kind of plague. Even those who recovered from the disease had much of their immunity and defences against respiratory infection so impaired that some people who felt well enough to return to work would quickly come down with a secondary infection of bacterial pneumonia which could kill them.

All of the resources of the new scientific medicine were thrown into the battle with the disease, with little or no impact upon its progression. The cause of influenza was not known at the time: some thought it was a bacterial disease while others suspected a virus. Further adding to the confusion is that influenza patients often had a secondary infection of bacterial pneumonia, and the organism which causes that disease was mis-identified as the pathogen responsible for influenza. Heroic efforts were made, but the state of medical science in 1918 was simply not up to the challenge posed by influenza.

A century later, influenza continues to defeat every attempt to prevent or cure it, and another global pandemic remains a distinct possibility. Supportive treatment in the developed world and the availability of antibiotics to prevent secondary infection by pneumonia will reduce the death toll, but a mass outbreak of the virus on the scale of 1918 would quickly swamp all available medical facilities and bring society to the brink as it did then. Even regular influenza kills between a quarter and a half million people a year. The emergence of a killer strain like that of 1918 could increase this number by a factor of ten or twenty.

Influenza is such a formidable opponent due to its structure. It is an RNA virus which, unusually for a virus, has not a single strand of genetic material but seven or eight separate strands of RNA. Some researchers argue that in an organism infected with two or more variants of the virus these strands can mix to form new mutants, allowing the virus to mutate much faster than other viruses with a single strand of genetic material (this is controversial). The virus particle is surrounded by proteins called hemagglutinin (HA) and neuraminidase (NA). HA allows the virus to break into a target cell, while NA allows viruses replicated within the cell to escape to infect others.

What makes creating a vaccine for influenza so difficult is that these HA and NA proteins are what the body's immune system uses to identify the virus as an invader and kill it. But HA and NA come in a number of variants, and a specific strain of influenza may contain one from column H and one from column N, creating a large number of possibilities. For example, H1N2 is endemic in birds, pigs, and humans. H5N1 caused the bird flu outbreak in 2004, and H1N1 was responsible for the 1918 pandemic. It gets worse. As a child, when you are first exposed to influenza, your immune system will produce antibodies which identify and target the variant to which you were first exposed. If you were infected with and recovered from, say, H3N2, you'll be pretty well protected against it. But if, subsequently, you encounter H1N1, your immune system will recognise it sufficiently to crank out antibodies, but they will be coded to attack H3N2, not the H1N1 you're battling, against which they're useless. Influenza is thus a chameleon, constantly changing its colours to hide from the immune system.

Strains of influenza tend to come in waves, with one HxNy variant dominating for some number of years, then shifting to another. Developers of vaccines must play a guessing game about which you're likely to encounter in a given year. This explains why the 1918 pandemic particularly hit healthy adults. Over the decades preceding the 1918 outbreak, the primary variant had shifted from H1N1, then decades of another variant, and then after 1900 H1N1 came back to the fore. Consequently, when the deadly strain of H1N1 appeared in the fall of 1918, the immune systems of both young and elderly people were ready for it and protected them, but those in between had immune systems which, when confronted with H1N1, produced antibodies for the other variant, leaving them vulnerable.

With no medical defence against or cure for influenza even today, the only effective response in the case of an outbreak of a killer strain is public health measures such as isolation and quarantine. Influenza is airborne and highly infectious: the gauze face masks you see in pictures from 1918 were almost completely ineffective. The government response to the outbreak in 1918 could hardly have been worse. After creating military camps which were nothing less than a culture medium containing those in the most vulnerable age range packed in close proximity, once the disease broke out and reports began to arrive that this was something new and extremely lethal, the troop trains and ships continued to run due to orders from the top that more and more men had to be fed into the meat grinder that was the Western Front. This inoculated camp after camp. Then, when the disease jumped into the civilian population and began to devastate cities adjacent to military facilities such as Boston and Philadelphia, the press censors of Wilson's proto-fascist war machine decided that honest reporting of the extent and severity of the disease or measures aimed at slowing its spread would impact “morale” and war production, so newspapers were ordered to either ignore it or print useless happy talk which only accelerated the epidemic. The result was that in the hardest-hit cities, residents confronted with the reality before their eyes giving to lie to the propaganda they were hearing from authorities retreated into fear and withdrawal, allowing neighbours to starve rather than risk infection by bringing them food.

As was known in antiquity, the only defence against an infectious disease with no known medical intervention is quarantine. In Western Samoa, the disease arrived in September 1918 on a German steamer. By the time the disease ran its course, 22% of the population of the islands was dead. Just a few kilometres across the ocean in American Samoa, authorities imposed a rigid quarantine and not a single person died of influenza.

We will never know the worldwide extent of the 1918 pandemic. Many of the hardest-hit areas, such as China and India, did not have the infrastructure to collect epidemiological data and what they had collapsed under the impact of the crisis. Estimates are that on the order of 500 million people worldwide were infected and that between 50 and 100 million died: three to five percent of the world's population.

Researchers do not know why the 1918 second wave pathogen was so lethal. The genome has been sequenced and nothing jumps out from it as an obvious cause. Understanding its virulence may require recreating the monster and experimenting with it in animal models. Obviously, this is not something which should be undertaken without serious deliberation beforehand and extreme precautions, but it may be the only way to gain the knowledge needed to treat those infected should a similar wild strain emerge in the future. (It is possible this work may have been done but not published because it could provide a roadmap for malefactors bent on creating a synthetic plague. If this be the case, we'll probably never know about it.)

Although medicine has made enormous strides in the last century, influenza, which defeated the world's best minds in 1918, remains a risk, and in a world with global air travel moving millions between dense population centres, an outbreak today would be even harder to contain. Let us hope that in that dire circumstance authorities will have the wisdom and courage to take the kind of dramatic action which can make the difference between a regional tragedy and a global cataclysm.