Rosa Brooks, a law professor at Georgetown University and a senior fellow at the New America Foundation, was an Obama administration appointee at the Defense Department from 2009 to 2011. She is married to an Army Special Forces officer.

Each time I hear President Obama assure us that there will be “no boots on the ground” in Iraq or Syria, I think of my husband’s Army boots, lying in a heap in the corner of the downstairs study. They’re covered in fine dust from his latest Middle East deployment, one that came nail-bitingly close to being extended by an unplanned stint in Iraq.

In the end, he wasn’t sent back to Iraq. He came home in July, though a last-minute change in assignments left most of his civilian clothes stranded in some Army transport netherworld. Deprived of his sneakers and sandals, he wore his Army boots pretty much everywhere this summer, even on playground outings with the kids. Watching grass stains from the local park gradually displace nine months of Kuwaiti dust gave me more happiness than I can say.

Even so, I can’t help feeling queasy every time I hear the president pledge that there will be “no boots on the ground” in America’s newest war. I wonder what that pledge really means — and just why we’re supposed to find it reassuring. It’s a pledge that seems to have everything to do with politics and little to do with the imperatives of strategy or security.

Here’s what “no boots on the ground” apparently doesn’t mean: It doesn’t mean that no U.S. troops will be sent to Iraq or Syria. Reportedly there are already 1,600 U.S. military personnel in Iraq. True, they’re present in an “advisory” role, not in a combat role — but surely one lesson of Iraq and Afghanistan is that combat has a habit of finding its way to noncombat personnel. Enemy snipers and IEDs don’t much care about a soldier’s mission or occupational specialty, and you can bet that fighters of the self-proclaimed Islamic State would be content with the heads of a few American advisers.

It’s also hard to know what publicly reported troop numbers really mean. When the Pentagon issues a Boots on the Ground report (known colloquially as a “BOG report”), it often excludes military personnel on “temporary duty” in combat areas, even though temporary duty may mean an assignment spanning five or six months. Similarly, Special Operations personnel assigned to work under CIA auspices are often left out of the BOG numbers. This makes it hard to know just who’s being counted when officials say there are 1,600 military personnel in Iraq.

“No boots on the ground” also ignores the many nonmilitary American boots (and shoes and sandals) present in Iraq and Syria. Our Baghdad embassy personnel presumably wear some kind of footwear, as do thousands more civilians working as U.S. government contractors in Iraq. In both Iraq and Syria, scores of American civilians also work for nongovernmental organizations and humanitarian aid groups.

The Pentagon keeps careful count of dead and wounded U.S. troops, but the government doesn’t systematically track dead or injured civilians or contractors (many of whom, of course, are U.S. military veterans). Though few Americans know it, there were often more contractors working for the U.S. government on the ground than there were U.S. troops at the height of the Iraq and Afghanistan wars, and some estimates suggest that there were as many U.S.-employed contractors who died in those conflicts as there were U.S. troops killed.

Cynics might even suspect that this heavy reliance on contractors was part of an effort to keep those BOG numbers down while outsourcing military risk. After all, no one likes high BOG numbers — the very acronym is suggestive of that most dreaded military outcome, the “quagmire.”

If “no boots on the ground” means playing games with numbers and offloading military risk onto U.S. government civilians and contractors, we should take little solace in presidential reassurances.

And we should feel even less comfort if “no boots on the ground” ends up putting vulnerable local civilians at risk. Remember Kosovo? President Bill Clinton’s refusal in 1999 to put U.S. troops on the ground forced us to rely solely on airstrikes to prevent Serbian ethnic cleansing. To further minimize any risk to U.S. military personnel, we mainly flew sorties at a safe 15,000 feet above the ground. This worked out well for us: Aside from two Americans killed in a helicopter accident in Albania, there were no U.S. fatalities in the 78-day air campaign. It worked out less well for some of the civilians we were trying to protect; in several cases, for instance, NATO pilots mistook convoys of refugees for troop transports, causing scores of civilian deaths.

The primary goal of the current U.S. airstrikes in Syria and Iraq isn’t civilian protection, but Obama has suggested that this is at least a secondary motivation. In his speech this past week to the U.N. General Assembly, for instance, he asserted that the Islamic State “has terrorized all who they come across in Iraq and Syria. Mothers, sisters and daughters have been subjected to rape as a weapon of war. Innocent children have been gunned down. . . . Religious minorities have been starved to death. In the most horrific crimes imaginable, innocent human beings have been beheaded. . . . The only language understood by killers like this is the language of force. So the United States of America will work with a broad coalition to dismantle this network of death.”

It’s hard to argue with the importance of dismantling a “network of death,” but no matter how careful we are, U.S. airstrikes in Syria and Iraq will also end up killing some innocent civilians. Without eyes and ears on the ground, we’re more likely to make tragic targeting mistakes. We have to hope we’ll do more good than harm, but it’s hard to feel confident of that.

Numerous respected military and defense leaders — from Army Gen. Martin Dempsey , current chairman of the Joint Chiefs of Staff, to retired defense secretary Robert Gates — have argued in recent weeks that ground troops will probably be required if our strategy is to be effective. So far, events seem to be proving them right: In Iraq, seven weeks of airstrikes have done little to push Islamic State fighters out of the territories they control, despite close U.S. coordination with Iraqi army units. In Syria, we have no similar local force with which to coordinate, creating a risk that U.S. airstrikes will increase the chaos without fundamentally reducing the threat to local civilians — or, in the longer term, to the United States.

And that’s most worrisome of all — the possibility that our insistence on “no boots on the ground” also offloads present risks onto the future. Relying on airstrikes alone may merely prolong a bloody and inconclusive conflict, or strengthen other actors who are just as brutal as Islamic State fighters, from the regime of Bashar al-Assad to the al-Qaeda-linked rebels of Jabhat al-Nusra.

Insisting that we’ll never commit U.S. troops to this fight plays right into every jihadist narrative, reinforcing America’s image as an arrogant but cowardly nation — happy to drop bombs from a distance but unwilling to risk the lives of our troops. Each time we reinforce that narrative, we give jihadist recruiting another big boost.

For a decade, we’ve relied on drone strikes as a top counterterrorism tool in Pakistan, Yemen and Somalia, but a few thousand dead terrorism suspects later, it’s far from clear that we’ve made ourselves safer. If anything, the global jihadist movement appears to have gained strength. As a former Defense Intelligence Agency director, Lt. Gen. Michael Flynn, recently noted: “In 2004, there were 21 total Islamic terrorist groups spread out in 18 countries. Today, there are 41 Islamic terrorist groups spread out in 24 countries.” Ultimately, our efforts to destroy the Islamic State from afar may similarly spark the creation of even more jihadist groups.

“I will not commit you . . . to fighting another ground war in Iraq,” Obama told troops at Central Command headquarters this month. I appreciate his desire to do right by America’s military personnel: My husband’s boots, like those of so many other members of the armed forces, have already gathered too much dust in too many dangerous places, over too many years. Right now, I want those boots to stay exactly where they are: here, at home.

But I don’t want to trade the safety of U.S. troops today for the safety of our children tomorrow. If Obama’s promise of “no boots on the ground” means we’ll be fighting a war of half-measures — a war that won’t achieve our objectives and that may increase the long-term threat — I’m not sure, in the end, that it’s a promise I want him to keep.

Twitter: @brooks_rosa

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