If you own a computer and know where to look  you've probably heard that there isn't actually any evidence for that claim.
Below are 10 reasons why this latest excuse for war is no good EVEN IF TRUE.
1. War is not made legal by such an excuse. It can't be found in the Kellogg-Briand Pact, the United Nations Charter, or the U.S. Constitution. It can, however, be found in U.S. war propaganda of the 2002 vintage. (Who says our government doesn't promote recycling?)
2. The United States itself possesses and uses internationally condemned weapons, including white phosphorus, napalm, cluster bombs, and depleted uranium. Whether you praise these actions , avoid thinking about them, or join me in condemning them, they are not a legal or moral justification for any foreign nation to bomb us, or to bomb some other nation where the U.S. military is operating. Killing people to prevent their being killed with the wrong kind of weapons is a policy that must come out of some sort of sickness. Call it Pre-Traumatic Stress Disorder.
3. An expanded war in Syria could become regional or global with uncontrollable consequences. Syria, Lebanon, Iran, Russia, China, the United States, the Gulf states, the NATO states . . . does this sound like the sort of conflict we want? Does it sound like a conflict anyone will survive? Why in the world risk such a thing?
4. Just creating a "no fly zone" would involve bombing urban areas and unavoidably killing large numbers of people. This happened in Libya and we looked away. But it would happen on a much larger scale in Syria, given the locations of the sites to be bombed. Creating a "no fly zone" is not a matter of making an announcement, but of dropping bombs.
5. Both sides in Syria have used horrible weapons and committed horrible atrocities. Surely even those who imagine people should be killed to prevent their being killed with different weapons can see the insanity of arming both sides to protect each other side. Why is it not, then, just as insane to arm one side in a conflict that involves similar abuses by both?
6. With the United States on the side of the opposition in Syria, the United States will be blamed for the opposition's crimes. Most people in Western Asia hate al Qaeda and other terrorists. They are also coming to hate the United States and its drones, missiles, bases, night raids, lies, and hypocrisy. Imagine the levels of hatred that will be reached when al Qaeda and the United States team up to overthrow the government of Syria and create an Iraq-like hell  in its place.
7. An unpopular rebellion put into power by outside force does not usually result in a stable government. In fact there is not yet on record a case of U.S. humanitarian war benefitting humanity or of nation-building actually building a nation. Why would Syria, which looks even less auspicious than most potential targets, be the exception to the rule?
8. This opposition is not interested in creating a democracy, or -- for that matter -- in taking instructions from the U.S. government. On the contrary, blowback from these allies is likely. Just as we should have learned the lesson of lies  about weapons by now, our government should have learned the lesson of arming the enemy of the enemy long before this moment.
9. The precedent of another lawless act by the United States, whether arming proxies or engaging directly, sets a dangerous example to the world and to those in Washington for whom Iran is next  on the list.
10. A strong majority of Americans, despite all the media's efforts thus far, opposes  arming the rebels or engaging directly. Instead, a plurality supports providing humanitarian aid.
We might better spread democracy by example than by bomb.
There are nonviolent pro-democracy movements in Bahrain and Turkey and elsewhere, and our government doesn't lift a finger in support.
But if you remember all those years of protesting wars and wishing millions of foolish partisan Republicans would join us in protesting blatant mass-murder even though the president was a Republican, I have good news for you. The Republicans are leading  the way in pretending to oppose war this time. So, if you Democrats, who I'm sure were 100% sincere in opposing wars some years back are still ready to act, maybe -- just maybe -- we can build  right now the sort of broad movement we've wanted.
If you're not too busy.