A year ago, on August 20, 2012, President Barack Obama remarked in an impromptu White House press conference that the Assad regime in Syria had been warned that, in the event of the repositioning or use of chemical weapons, a red line would be crossed and there would be “enormous consequences.” Obama’s warning extended to “other players on the ground,” that is, rebel forces or any other belligerents involved in the Arab Spring insurrection that had started with peaceful protests in March 2011 and then escalated into a civil war.

From December 2012 through May 2013, 19 small, dispersed chemical attacks were reported out of Syria. The fragmentary evidence, including dramatic images of victims foaming at the mouth, suggested the use of the nerve agent sarin or perhaps tear gas or other poisons. The rebels blamed the Syrian army. The Syrian army blamed the rebels. At one point, a finger was pointed at Hezbollah, Syria’s ally in putting down the insurrection, which reportedly had acquired a cache of mustard gas.

In June of this year, the United Nations expert commission on the Syrian crisis declared that it was of “the utmost importance” that UN investigators be allowed full access to four sites (two in Aleppo, one in Utelbah, Damascus, and another in Saraqib, Idlib) to investigate the claims. It declared that there were “reasonable grounds to believe that limited quantities of toxic chemicals were used.”  That same month, the news broke that the French Ministry of Defense had analyzed samples of urine from three victims of an alleged attack in the Jobar neighborhood of Damascus and found the chemical IMPA (isopropyl methylphosphonic acid), a marker for inhaled sarin. Just last month, United Nations investigators were given permission for access to the Syrian sites. They would be looking for environmental samples, munitions, clinical samples, documents, credible eye-witness accounts—in short, everything that would identify the agents and how and where the alleged attacks took place. Then, in the early morning hours of August 21, a mass use of poisons against civilians occurred in the suburbs of Damascus; the death count was put at over 300, with many more injured. The UN team, already in Syria, was diverted to this more pressing inquiry. Snipers interrupted their convoy’s first foray into the affected area but not its second, and the team now hopes for another four days of investigation, after which the samples it gathers will be tested at independent certified laboratories.    

This is the story so far, but its beginning goes back nearly a hundred years, to the Great War and the battlefield at Ypres in Belgium. There, on April 22, 1915, the German Army launched the world’s first successful use of chemical weapons, against British and French troops. After positioning nearly six thousand canisters of chlorine along the four-mile front, German officers waited until 5 p.m., when the prevailing wind shifted toward the enemy trenches. Then, in a synchronized movement, they released the toxic gas. Within minutes, six thousand of those targeted died from suffocation while others, forced from their trenches, were exposed to German gunfire. This signal event led to the massive use of chemical weapons on all sides, as the Germans, the British, the Italians, and the Russians each tried different toxic compounds. The term “weapons of mass destruction” and “arms race” had not yet been invented, but, like biological and nuclear weapons to come, chemicals promised a battlefield scenario that could make guns and mortars obsolete: a surprise attack on the unprotected foe would make them fall dead in heaps or stagger about burnt and blinded.

Since Ypres, the idea of chemical weapons (CW) has prompted more revulsion than enthusiasm. For soldiers in World War I, their exposure to chlorine, phosgene, mustard gas, and other poisons added to the already horrendous experience of trench warfare. When Wilfred Owen, the British poet of the battlefield, described his comrades “drowning in a yellow sea,” he captured an image that many brought back from the war. After the war’s end, in part because of strong public reaction, the major powers took the lead in promoting international restraints on these new weapons. The result was the 1925 Geneva Protocol, which bans the use of chemical and also bacteriological weapons in war, but it also did allow retaliation in kind and arsenals for defense against aggressors. 

Fast forward to World War II and one finds that, oddly enough, both the Allies and the Axis powers refrained from using chemical weapons to attack each other, although they had CW arsenals as well as a new capability for strategic aerial bombing and other total war attacks. Fear of retaliation may explain why Imperial Japan and Nazi Germany refrained from attacking the Allies with chemicals. President Roosevelt warned each that if they did, the United States would make them regret it. 

And perhaps revulsion played a part, at least in the United States’s decision not to use chemical weapons. For certain U.S. commanders, a surprise attack on unprotected soldiers was unprincipled. Admiral William Leahy, a close advisor to Roosevelt, told the president that massive use of either chemical or germ weapons would violate Christian ethics and all the known laws of war. “It would be,” he added, “an attack on the non-combatant population of the enemy.” Like Japan, the United States had not ratified the Geneva Protocol and could with some impunity engage in a first strike. But Leahy warned, “The reaction can be foretold—if we use it, the enemy will use it.”  

But the best explanation for why chemical arsenals were not used may be that by the 1940s weapons of land warfare had improved technologically, leaving CW outmoded. Air power, better tanks and mortar, and, in the United States, the development of incendiaries such as napalm (not categorized as chemical weapons) promised more battlefield success than chemicals. Even in World War I, the drawbacks of CW had become obvious. Wind currents proved unreliable—one’s own soldiers might be killed or sickened by “blow back,” and enemy troops were increasingly defended by gas masks, protective suits, and blankets. Why load a bomber with heavy chemical munitions when, pound for pound, high explosive bombs had more predictable devastating effects? In the background loomed the even greater potential of the U.S. atomic weapons program, and, equally secret, the development of its biological weapons for mass offensive attacks. Following the U.S. atomic bombings of Hiroshima and Nagasaki, chemical and biological weapons (in which the United States had made a great investment) both paled in comparison, but only temporarily. 

As the war in Europe ended, the Allies discovered that Nazi chemists had invented the lethal nerve gases sabin and tabun. These paralyzing agents, causing quick and certain death, revitalized the development of chemical weapons. In 1945, the United States, economically strong and scientifically superior, had little sense that the dangerous weapons it pioneered would proliferate globally. But on September 23, 1949, when President Truman announced that the Soviet Union had successfully tested its first atomic bomb, the Cold War arms race began in earnest. In response, along with its nuclear weapons development, the U.S. Army began building up its chemical arsenal and expanding its germ weapons program to an unprecedented scale, involving dozens of universities and industries and testing areas in the United States and Canada.   

The Cold War saw an extraordinary amassing of nuclear, chemical, and biological weapons by American and Soviet militaries, with the United Kingdom and France following suit. Then less wealthy nations in troubled world areas entered the WMD arms race: China, Israel, India, Pakistan, apartheid South Africa, Iraq, Libya, and others. For Israel, the possession of WMD became integral to its defense policy and it never ceased to monitor its neighbors’ ambitions. In 1982, Israeli military intelligence reported that Egypt had supplied chemical weapons to Syria. In a short time, Syria, concentrating on chemicals, developed its own significant CW capability. The rationale, later publicly expressed by President Hafez al-Assad (father of the current president, Bashar al-Assad), was that Syria needed chemicals as a deterrent to nuclear attack by Israel. Meanwhile, in Iraq, U.S. ally Saddam Hussein bragged about his WMD arsenal and did not hesitate to use chemical weapons during the long Iran-Iraq war in the 1980s, which included the killing of Kurdish civilians with nerve gas at Halabja.

The end of the Cold War abruptly changed the world’s approach to  CW . On January 13, 1993 in Paris, representatives from over a hundred nations gathered to sign the Chemical Weapons Convention (CWC). This international ban on the development, production, possession, transfer, and use of these weapons had been strongly promoted by President George H. W. Bush, who has never received the credit he deserves for this accomplishment. The event in Paris was joyful. The Cold War was over. Saddam Hussein, his fortunes reversed, had been restrained by the cease-fire terms of the Gulf War. The United States and Russia agreed to the destruction of their chemical arsenals—in line with the joint reduction of their nuclear stockpiles—and set an example for other nations to do the same. The treaty created the Organization for the Prohibition of Chemical Weapons, which, under UN supervision, would oversee the destruction of state CW arsenals and provide trained teams of inspectors in cases of possible treaty violations. It looked as if chemical weapons had been consigned to the junk heap of history. But, as we know now, their danger persisted..  

Israel signed the treaty, but failed to ratify it, and so was not a party to it. Egypt and Syria turned their backs entirely. It should have been possible at the time for the United States and Russia to pressure these three small nations, each known to possess chemical weapons, to join the treaty and agree to destroy their stockpiles. But the heedless presumption of the major powers seemed to be that the state governments in the Middle East were stable enough, that their relations with one another, even if marked by frequent violent conflicts, were unlikely to change significantly. Perhaps no leader in the region was more surprised by the 2011 protests for democracy than President Assad, whose father had ruled the country for thirty years (1970-2000) and who himself must have expected a long rule.

In the 1990s, Syria—a Middle Eastern power with Russia as its ally—was immune to outside intervention from the West. Today, however, Syria is shunned by the Arab League and its regional clout and guarantee against intervention have evaporated. Even with proof still incomplete, U.S. Secretary of State John Kerry and Vice-President Joe Biden have each recently told the media that they believe Syria has used chemical weapons against civilians and must be held accountable. The implication is that, as Russia and China on the United Nations Security Council continue to block military intervention by a UN coalition, the United States would proceed without it.  In contrast, the majority of Americans are against such military engagement, and with good reason. U.S. bombs and missiles have done little over the years to solve the problems of Iraq or Afghanistan. Ethnic, religious, and regional antagonisms in the region are complicated. Consider the current hostile divides between Iraq’s Sunni, Shiite, and Kurdish populations.  Syria’s present conflict shows signs of a similar breakdown: a Kurdish stronghold is developing in the northeast; the areas around Damascus, Homs and the Mediterranean are under Assad’s control; and disparate rebel forces dominate from Aleppo along the Euphrates Valley to Iraq.   

President Assad is being portrayed as a cruel despot. He is sometimes depicted as following in the footsteps of his father, who in 1982 authorized the slaughter of thousands of insurgent Sunnis, perhaps with the use of cyanide gas. But the truth about Assad and CW use earlier this month may be more complex. Just before the 2003 US invasion of Iraq, for example, the testimony of defectors about Saddam’s WMD proved highly unreliable. Still, two Syrian defectors interviewed this past spring (one by a Dubai news channel and the other by Al Jazeera) agreed that, rather than mass attacks, the Syrian army had formulated a doctrine for limited use of CW, usually sarin, to disperse insurgents while keeping death counts low. One of the defectors, a scientist, said that experimental mixtures of sarin and tear gas and other chemicals were intended to confuse observers. If so, what sudden turn of events caused the August 21 mass attack? Was it a change in military doctrine, a misadventure, rebel subterfuge, foreign terrorists, an internal plot, or, as has been recently suggested, intervention by Maher al-Assad, the president’s brother?

UN inspectors are now searching for evidence in a war zone, the worst imaginable context for rational inquiry. Their situation is made even more precarious by the fact that the evidence they collect may point to the army of the host government, the Syrian Arab Republic. Figuring out who is guilty is not part of the UN mission, but on the basis of environmental and clinical evidence and the identification of munitions, Syria’s military officers and President Assad could eventually be held legally liable in an international court.

When the present crisis in Syria is resolved, as inevitably it will be, the CWC must be made universal.  It almost is: 188 states adhere to it; 7 are holdouts (Israel, Syria, Egypt, Myanmar, Angola, North Korea, and South Sudan). Syria must allow its chemical weapons to be identified, contained, and destroyed. It should have been done years ago. Israel and Egypt must also be persuaded to join the treaty and comply with it, before more chaos erupts. “Almost universal” is simply not good enough.

Admiral Leahy was right about the repulsive nature of chemical weapons and the danger they pose to civilians. It is time that the epoch that began with Ypres should end for good.