For all his stirring rhetoric about ending America's decade of war, President Obama appears intent on extending it for several years more. A missile strike against Syrian targets will not result in Bashar Assad's removal from power any more than the Clinton-era strikes against Afghanistan and Sudan resulted in regime change in those countries. On the other hand, full-scale Western intervention in the Syrian civil war, at a minimum along the lines of the 2011 operation against Libya's Muammar Gaddafi, will provide Russia on the one hand, and Iran and Hezbollah on the other, the excuse for even more intense and open support of the Assad regime. Indeed, Hezbollah, with Iranian connivance, is likely to retaliate against American military or even civilian targets elsewhere in the world.

And what if Assad were to depart the scene, and the rebels were to seize power? As Seth Jones of RAND, one of the most respected analysts of insurgencies has pointed out, the most formidable rebel group is Al Nusra, the Al Qaeda-linked Salafi group. Al Nusra may not be the largest rebel faction, but it is the best organized, and its superior organization will no doubt enable it to come out on top in any post-Assad struggle for power. That, of course, is how the Bolsheviks came to dominate Russia for eighty years. And should the Islamists seize power, the days of Hashemite rule in Jordan, America (and Israel's) closest Arab ally, may well come to an end.

The Administration's case for intervention—Assad's employment of chemical weapons—is flimsy at best. The United States did not intervene when Saddam Hussein employed chemical weapons against his own people. What has changed since then? Some who press the case for a strike against Syria argue that the international community now has accepted the "responsibility to protect" citizens against their governments. Why wasn't that responsibility taken seriously vis a vis Syria until now? Why should action be taken when the Assad regime kills a thousand people, but nothing done during the past two years, when that regime annihilated one hundred thousand of its citizens? Moreover, it should not be forgotten that not only has Washington tolerated the use of chemical weapons by a government against its citizens, it actually supported Saddam even as he fired chemical weapons in his war with Iran.

Some have argued, prominent among them Israeli prime minister Benjamin Netanyahu, that were Assad to "get away" with using chemical weapons, Iran would conclude that the West is toothless in the face of any outrage, and would never back away from its nuclear weapons program. In fact, the opposite is likely to be the case. On the one hand, the consequences for international security of the civil war in Syria can in no way be compared to those arising from Iran going nuclear. The Syrian war is an internal affair. Should Assad prevail, the likelihood of spillover to neighboring countries is minimal, nor is Israel likely to strike Damascus. He will at best be a weakened force and will have to concentrate on his domestic challenges.

In contrast, Iran's nuclear weapons program is very much an international matter. Tehran is perceived as intending to employ nuclear weapons not against its own people, but against the populations of other states, notably Israel. It is for that reason that the closer Iran comes to developing a bomb, the more likely it is that Israel, or America, or both, and perhaps with the assistance of others, would launch a strike against its nuclear facilities. In light of ongoing sanctions and the threat of a military strike, the incentive for Iran to negotiate an agreement would in no way have been diminished, regardless of whether Assad prevails.

Ironically, should Assad fall, there is virtually no chance that Iran would agree to halt its program. Having watched the United States change yet another Middle Eastern regime, the ayatollahs would conclude once and for all that the only way to survive is to follow the example of North Korea and both acquire and then brandish a nuclear capability as soon as possible.

It is troubling that the Obama Administration continues to be short on its knowledge of Middle Eastern attitudes and history; Middle Easterners—and, for that matter, the Russians and Chinese—are not. A U.S. attack will be seen by all sides as yet another assault on Muslims, and another attempt by Washington to dominate the Middle East and mold it in its own image. American influence in the region will inevitably decline still further.

Lastly, any strike on Syria, which could cost hundreds of millions of dollars at a time when the U.S. defense budget is being ruthlessly pared back, may only be a down payment if the Assad regime continues to press on with its offensive. There is no guarantee that the United States and its allies will not find themselves drawn into a much longer and costlier operation than the White House anticipates. The Libya operation cost America well over a billion dollars, and exhausted the resources of France and especially Britain. Compared to what might be required in Syria, Libya was a budgetary bargain. How the president would propose to finance a prolonged Syrian exercise in the face of the ongoing sequester is a question that remains to be addressed.

President Obama spoke too hastily when he described the use of chemical weapons in Syria as a "red line." He should not compound that mistake by engaging Syrian forces (and perhaps their Russian advisors) in military hostilities whose duration and consequences are in no way predictable. Now is the time for restraint, not military action; the president should lead accordingly, and not from behind either.

Dov Zakheim served as the undersecretary of defense (comptroller) and chief financial officer for the U.S. Department of Defense from 2001–2004 and as the deputy undersecretary of defense (planning and resources) from 1985-1987. He also served as DoD's civilian coordinator for Afghan reconstruction from 2002–2004. He is a member of The National Interest's advisory council.