That's what one U.S. official says about the prospect that Syria's vast stockpile of chemical weapons might be used against rebel forces. From a U.S. national security standpoint, an even worse outcome would be for those weapons to fall into the hands of terrorists.
"Syria has probably the largest and most advanced chemical warfare program in the Arab world, " Michael Eistenstadt, director of the Military and Securities Studies Program at the Washington Institute for Near East Policy, said in a report released this week, adding that the country is able to fill thousands of missiles and artillery shells with chemical agents.
"Washington should begin planning to locate, secure and eliminate Syria's chemical stockpile and infrastructure should the regime lose control of chemical weapons facilities or fall outright," says Eisenstadt.
So what is President Bashar Assad's regime believed to have?
They include VX and sarin nerve agents, the most toxic of all chemical weapons, according to Charles Blair, an analyst with the Federation of American Scientists.
Nerve agents are what Iraqi dictator Saddam Hussein used to kill thousands of Kurdish men, women and children in one town in northern Iraq in 1988.
The Syrians are also thought to have mustard agent, the kind used by the Germans during World War I, which can create blisters in the lungs. The Syrians are thought to have several hundred tons of it.
American military officials say the Syrians also have thousands of Scud missiles and artillery shells that can be filled with these chemicals.
While U.S. security officials have expressed serious concerns, the Obama administration and military officials so far haven't given any indication that they would favor sending forces into Syria to try to confiscate or safeguard those weapons.
One problem for the U.S. and its allies is that there are an estimated 50 chemical storage facilities in Syria, and the Pentagon projects it would take thousands of U.S. military personnel to guard them.
Right now, the U.S. is keeping a close eye on those chemical weapons, presumably using satellites and other intelligence means. The Wall Street Journal recently reported that the Syrian government has started to move some of its stockpile. But it's uncertain if that movement — which the US has not confirmed — is designed to better secure the weapons or get them ready to use against rebel forces.
"We're well aware that Syria has large stockpiles of chemical weapons," the US Ambassador to the UN, Susan Rice, told All Things Considered. "Syria has a legal and moral obligation to secure them. ... Should anyone in the Syrian regime do otherwise, they will be held accountable."
So what are the options if the Syrians are not responsible, or if the country fractures and the armed forces start losing control of the chemical weapons?
The Pentagon is briefing Congress on the situation and the possible options.
Some analysts say the U.S. or Israel could bomb suspected chemical sites. However, some chemicals would be released into the air and endanger nearby civilians. It's also unlikely all the weapons would be destroyed, leaving them vulnerable to loss of theft.
Sending in specialized military teams, from either the U.S. or an ally, is also an option. And one military official says it would take thousands of troops, who could come not only from the US but Israel, Jordan and Turkey.
A third possibility, officials say, involves reaching out to officials within the Syrian military and urging them to continue to secure the sites – maybe giving them money — especially if the government starts to crumble.
CIA officers in Libya worked with officials in that country to secure its chemical weapons sites, though that was after Moammar Gadhafi fell from power last year. And experts say the majority of those weapons already had been destroyed by Gadhafi years earlier as he tried to make better relations with the international community.
The good news is that Syria has never before used chemical weapons. The bad news is that Nawaf al-Fares, who was Syria's ambassador to Iraq until his recent defection, said he believed the Assad regime would be willing to use them if cornered.
NPR's Tom Bowman has covered the Pentagon and the U.S. military since 1997.