Syria is already mired in civil war. To stop that conflict through military intervention would require substantial numbers of ground troops and the political and domestic will to stay there for a very long time. All this would take place in the face of other actors in the region who might not want the United States there and would be prepared to fight.

The idea that stopping the civil war in Syria and protecting its population can be done on the cheap—via drones policing enclaves and humanitarian corridors—is military dilettantism gone wild.

To suggest that Syria is not mired in a violent civil war, that it is only in the preliminary stages of what might become an internal conflict, is naive and misinformed. Former Sunni soldiers have departed their army units and taken up arms against the Assad government. These Sunni fighters have both the moral and material support of significant parts of the Syrian population.

If this isn't civil war, I don't know what is. Idealistic foreign-policy experts who are actively calling for American military intervention in Syria to protect the vulnerable civilian population hesitate to use the term “civil war.” They know that if they do, the immediate response will be pessimistic: Why send the military into the middle of a brutal war between the peoples of Syria with little short-term chance of ending it?

Yet Syria is what it is, and we should be honest about all the proposals on the table as the United States considers its options.

The Idealist Proposal

Princeton professor Anne-Marie Slaughter has called for a military intervention of sorts to protect the part of the Syrian population being attacked by Assad's regime. Under her proposal, a coalition of countries (presumably the United States would play a key part) would establish enclaves around the edges of Syria. These safe havens would provide a place for the battered Syrian population to come for protection. The enclaves and their routes to cities like Homs would be protected by high-flying drones with access to foreign firepower and could be used to attack any Syrian forces that tried to eliminate the protected zones.

This scenario sounds utterly practicable as part of a theory conjured up in the comfort of the ivory tower. But in practice, Western military technology cannot stop messy civil wars in foreign lands. Ending the internal conflict in Syria and producing a peaceful aftermath would entail a long-term American commitment to armed nation building. The wars in Iraq and Afghanistan should have made this clear. Armed nation building isn't done in eight or eleven years but eighty or a hundred years beyond.

But here is where good strategy should kick in. Good strategy might and probably should discern that in these kinds of civil wars, considering U.S. security interests, using military force is not the solution. Force might be a good option if Americans were willing to stay for generations, but then strategy might also determine that a prolonged engagement is simply not worth it.

The Real Costs

The decision to apply military force in the way suggested by Slaughter is ultimately one for policy makers. I am a serving soldier obedient to my political masters. If President Obama directs the military to intervene to protect the Syrian people by stopping the civil war, then that is exactly what we shall do. Yet it is also the responsibility of the American military to provide realistic advice on what that will actually entail—and what it will cost.

Halting the civil war will require a generational effort and significant commitment of boots on the ground. I have been on the business end of an American military force placed in the middle of a civil war in a foreign land. In 2006, I commanded a combat battalion in western Baghdad in that most hellish year of Iraq's civil war between Sunni and Shia. Although my outfit's primary task was to "protect the Iraqi people," we invariably were forced to take sides.

There is much moral weight in "Responsibility to Protect" because the term implies that the foreign military force used to "protect" vulnerable civilians will be effective. Yet the hard hand of war does not always adhere to catchy, moralistic terms. Instead, when the United States applies military force to "protect," it takes part in the destruction, death and devastation of war. Thus the military ends up hurting the civilian population in the very process of trying to protect it. These kinds of interventions in civil wars are never as clean or clear as idealistic policy experts wish them to be.

If the civilian decision makers of United States decide to intervene in Syria to protect its population and end the civil war, the military will step up to the task. But policy experts should do so with a realistic sensibility of what an intervention will require: It won't be cheap. It won't be easy. It will take a very long time. And from the angle of U.S. national interests, it’s probably not worth the cost in American blood and treasure.

Gian P. Gentile is a serving army colonel. He holds a PhD in history from Stanford University. He has done two combat tours in Iraq, the second tour in West Baghdad in 2006 as a combat battalion commander.

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