Why the U.S. Military Can’t Fix Syria

The State Department “dissent channel” memo on the United States’ policy in Syria, leaked last month, is just the latest expression of a widespread belief in and out of government that American intervention in Syria is necessary and would be successful.

After five years of brutal, grinding war, this view is understandable. The idea of the United States saving the Middle East from itself appeals to liberal hawks and neoconservatives alike. Unfortunately, when that notion has carried the day — as it did in Iraq in 2003 and Libya in 2011 — regional security and stability have worsened. Indeed, in light of Syria’s geopolitical circumstances, intervention along the lines suggested in the memo could produce consequences more dangerous than those of the two previous adventures.

The memo’s authors and other interventionists fail to recognize that the United States in fact has effectively weakened President Bashar al-Assad already. In 2015, the administration’s aggressive covert action program facilitated significant gains for the opposition in northern Syria, exposed Latakia — the regime’s heartland — to attack, and diminished the Syrian military position in the northwestern province of Idlib.

But these losses were also key factors in Russia’s decision to enter the Syrian fray after years of sitting on the sidelines. This gives the lie to the interventionists’ belief that “judicious” airstrikes could somehow disempower the Assad government, sap Russian resolve and improve prospects for a negotiated solution.

If Moscow saw fit to intervene on account of Washington’s covert support for the rebels, it is only logical that it would retaliate even more strongly in the event of overt support. Indeed, that prospect is probably Moscow’s main motivation for keeping an air contingent and thousands of troops in Syria, conducting regular operations there and continuing to assure the Syrian government of Russia’s unstinting support.

Even in the unfathomable event that Russia were to abandon Syria, direct American military action would cause Iran and Hezbollah, the Assad government’s closest allies, to intensify their support. This would strengthen hawks in Iran and dim prospects for further improvement in United States-Iran relations.

Perhaps the interventionists believe that American military action would force Mr. Assad to the peace table. That prospect is equally implausible. There is no conceivable bargain that the Syrian president could strike with his adversaries, many of whom are hard-line Islamists. He and his colleagues would rather go down fighting than hand Syria to Sunni jihadists. The same goes for Iran and Hezbollah.

But the biggest problem with the arguments for intervention — even the calibrated airstrikes that the dissent channel memo calls for — is that it would lead to boots on the ground. Assuming Mr. Assad were to escalate attacks in response to the airstrikes — a virtual certainty — the option of a limited response would no longer be available.

For example, if the United States simply cranked up the pace and intensity of airstrikes with an eye to blunting Mr. Assad’s resistance, Russia, Iran and Hezbollah would be even more likely to come to his rescue. Washington would be left just two realistic options: stand down and look feckless or ratchet up the conflict into a full-blown proxy war and commit to finishing off the regime.

Direct military action against the Syrian government would ignore the primary lesson of Libya: that regime change, absent the willingness and capacity to engage in subsequent stabilization operations, opens the door to extremist groups. An American commitment to such operations in Syria would also ignore the primary lesson of Iraq: that true stabilization requires both counterinsurgency and state-building, for which the United States, like most mature democracies, lacks the stomach for brutality and political stamina.

More broadly, the signatories of the memo and their fellow travelers do not seem to appreciate that an American president has limited resources to fulfill global strategic commitments like countering China in the Pacific, strengthening NATO, and keeping nuclear weapons out of Iran’s hands. The president can’t afford to undertake an open-ended war in Syria, a country in which the United States’ national interest is subtle and complex. If the United States has a direct military interest in Syria, it is as a jihadist killing field. It is already advancing that interest via a sustained and effective air campaign against the Islamic State.

Beyond such realist considerations, the dissent channel memo defaults to general notions like the integrity of the “international system” for civilian protection and “accountability” for human rights violations. These are valid concerns, but they are strategically tertiary.

The memo also intimates that American restraint in Syria somehow puts the United States’ credibility on the line more broadly. This, too, is a stretch. Beijing is probably not looking at how Washington deals with Damascus, either ethically or operationally, to decide whether or not to seize Taiwan or assert control over the Malacca Strait. Within the Middle East, American restraint has not undermined the Sunni anti-Islamic State coalition, and is unlikely to do so. If anything, that coalition has strengthened over the past three years.

There is, of course, a strong American humanitarian interest in Syria and in helping allies and partners with the flow of refugees. Some 400,000 people have died, nearly 600,000 are starving and millions have been forced from their homes. Complacency about this terrible war would be completely unacceptable. But the United States has already allocated well over $5 billion to alleviate suffering and to support vulnerable friends like Jordan. American resources are better spent on sustaining a stricken population and regional governments’ needs while nurturing a political process on Syria, however tortuous, than on conducting futile military assaults against the regime.