In 2008, a secret State Department cable warned of a growing chemical weapons threat from a Middle Eastern country whose autocratic leader had a long history of stirring up trouble in the region. The leader, noted for his “support for terrorist organizations,” was attempting to buy technology from other countries to upgrade an already fearsome stockpile of deadly poisons, the department warned.

The Middle Eastern state with the dangerous chemicals was not Libya, whose modest stockpile was thrust into the spotlight last week because of fighting there. It was Syria, another violence-torn Arab state whose advanced weapons are drawing new concern as the country drifts toward an uncertain future.

A sudden collapse of the government of Syrian President Bashar al-Assad could mean a breakdown in controls over the country’s weapons, U.S. officials and weapons experts said in interviews. But while Libya’s chemical arsenal consists of unwieldy canisters filled mostly with mustard gas, the World War I-era blistering agent, Syria possesses some of the deadliest chemicals ever to be weaponized, dispersed in thousands of artillery shells and warheads that are easy to transport.

Syria’s preferred poison is not mustard gas but sarin, the nerve agent that killed 13 people and sickened about 1,000 during a terrorist attack on the Tokyo subway system in 1995. Sarin, which is lethal if inhaled even in minute quantities, can also be used to contaminate water and food supplies.

Although many analysts doubt that Assad would deliberately share chemical bombs with terrorists, it is not inconceivable that weapons could vanish amid the chaos of an uprising that destroys Syria’s vaunted security services, which safeguard the munitions.

“This is a scenario that’s on the radar screen if things go downhill,” said a U.S. security official who monitors events in Syria. “A lot of people are watching this closely.”

Deadly, large cache

Syria first developed chemical weapons in the 1970s and slowly amassed a sophisticated arsenal under the close supervision of then-President Hafez al-Assad and, later, his son Bashar, the current president. Using technology obtained in part from Russian scientists, the Assads sought to create a strategic deterrent against Israel, its vastly more powerful southern neighbor, whose forces humiliated Syrian troops in the 1967 Arab-Israeli war and captured the strategic Syrian plateau known as the Golan Heights.

Many countries, including the United States and Russia, gradually eliminated their chemical-weapons arsenals, but Syria refused to sign the U.N. Chemical Weapons convention and proceeded to develop an ever larger and deadlier stockpile. The CIA has concluded that Syria possesses a large stockpile of sarin-based warheads and was working on developing VX, a deadlier nerve agent that resists breaking down in the environment.

By early in the last decade, some weapons experts ranked Syria’s chemical stockpile as probably the largest in the world, consisting of tens of tons of highly lethal chemical agents and hundreds of Scud missiles as well as lesser rockets, artillery rockets and bomblets for delivering the poisons.

Jeffrey Feltman, the State Department’s chief diplomat for the Middle East, last year cited Syria’s chemical weapons program as a primary reason for continuing U.S. economic sanctions against the Assad regime.

“We will continue pressing the Syrian government on its problematic policies,” Feltman said in testimony before a House committee.

The 2008 State Department cable, obtained and made public by the anti-secrecy group WikiLeaks, was prompted by a Syrian attempt to obtain glass-lined reactors and other high-tech equipment from a private Indian firm. U.S. diplomats pressed the Indian government to block the sale. “We are concerned that the equipment in question is intended for, or could be diverted to Syria’s chemical weapons program,” the cable stated.

It was unclear whether the sale, which at the time was in its final stages, was allowed to proceed.

Dangerous ripple effects

Syria tops the list of Middle East countries with potentially vulnerable weapons systems, but U.S. officials say the political turmoil in the region has prompted a reassessment of the risks posed by arsenals elsewhere as well.

Several Middle Eastern countries possess large numbers of conventional weapons as well as nuclear research reactors whose fuel rods could be used in a “dirty bomb.” There is no evidence that advanced munitions have been stolen. But U.S. officials acknowledge increasing uncertainty about the control of weapons depots in countries undergoing prolonged periods of unrest.

Libya risk assessment

Western officials have been less concerned about Libya’s chemical stockpile, which was all but dismantled after Moammar Gaddafi agreed about eight years ago to renounce weapons of mass destruction. In reality, it was never especially impressive, having barely advanced beyond early 20th-century technology, weapons experts say. At the time Libyan rebels overran Gaddafi’s headquarters in Tripoli last week, the stockpile consisted of 11 metric tons of mustard agent and 845 tons of chemical precursors, none of it directly usable in weapons and all of it stored in steel barrels inside a fortified bunker.

“We assess that the facility is secure,” the State Department said Friday in a statement on the Libyan program.

U.S. officials said they were more concerned about safeguarding Libyan conventional weapons, including shoulder-fired antiaircraft missiles. U.S.-backed teams of weapons experts have been working in liberated areas of Libya since May to find the missiles, which are coveted by terrorists because they can be used to shoot down low-flying planes and helicopters.

The teams have been given $3 million to find the missiles, hundreds of which are said to exist in depots scattered throughout Libya.

The number destroyed so far: five.