U.S. soldiers in Iraq in 2008, using their boots Reuters

A president is axiomatically having a bad week when his understanding of warfare is criticized, in public, by the most revered living Marine general. This is what happened yesterday when retired Gen. James Mattis, the legendary former chief of U.S. Central Command, told the House Intelligence Committee that, “You just don’t take anything off the table up front, which it appears the administration has tried to do.”

Mattis is referring to President Obama’s promise to avoid deploying ground troops, no matter what, in the fight against the Islamic State terror group. (There are, of course, already U.S. troops wearing boots that touch the ground in Iraq, but they are not meant to join the frontline fight against ISIS, though they could obviously get hurt anyway, this being Iraq.)

Mattis's argument is simple: Never tell your enemy what you’re not going to do. “If this threat to our nation is determined to be as significant as I believe it is, we may not wish to reassure our enemies in advance that they will not see American boots on the ground,” Mattis said. “If a brigade of our paratroopers or a battalion landing team of our Marines would strengthen our allies at a key juncture and create havoc/humiliation for our adversaries, then we should do what is necessary with our forces that exist for that very purpose.”

Even Gen. Martin Dempsey, the Joint Chiefs chairman, who is not a lean-in sort of commander in the Mattis style, has acknowledged the possibility of an eventual need for ground troops.

President Obama’s caution in the matter of ISIS is not the disaster many people make it out to be—his sobriety and thoughtfulness may one day be remembered more fondly than they are understood now—for a couple of reasons: The first is that ISIS doesn’t pose an immediate threat to the United States, because, unlike al-Qaeda, it is mainly interested in building up its own state, not in attacking the far enemy. Unlike many of his fellow countrymen, Obama hasn’t let anger over the beheadings of two Americans blind him to the current nature of the threat. The second is that he has a proper appreciation for the limitations of American allies in the Middle East, and he knows that true victory against ISIS will only come when our allies are capable of taking the lead in this struggle. It doesn’t matter, in other words, if Obama puts 20,000 troops, or 200,000, into this fight. Without capable partners to secure the victory these troops would obtain, there’s no point in making such a commitment.

But: Obama has committed himself to the eventual destruction of ISIS, and so it is counterproductive strategically to signal to ISIS his plans and intentions.

There is a way for Obama to reframe the American role in the fight against ISIS, without committing to any specific course of action. I didn’t come up with this new rhetorical and policy path; Obama did, in interviews with me, and others, and in public statements over the past several years. The subject of these interviews and public statements was not the threat posed by Sunni radicalism, but the threat posed by the Shiite revolutionary state, Iran. When asked what he would do to stop Iran from gaining possession of a nuclear weapon, Obama always answered the same way: “All options are on the table.”

“All options on the table” has an ominous ring to it. It is concise, ambiguous, and threatening, and I believe that its regular public deployment was one factor that motivated Iran to negotiate the future of its nuclear program with the U.S., rather than continue its rush to the bomb.

Using this slogan—as opposed to “no boots on the ground”—in the case of ISIS would also have the advantage of being accurate, because of course there are situations in which President Obama may have to use ground troops in the struggle against ISIS, particularly if U.S. assets, or allies, are directly threatened. Does anyone really believe that if ISIS were to make a move on Baghdad, which is home to the largest U.S. embassy in the world, or on Jordan, that the president wouldn’t use whatever force necessary prevent a debacle?

A move from “no boots on the ground” to “all options on the table” would cause the Consistency Police (i.e. my profession) to go berserk, and would frighten the left, and also the non-interventionist right. But the decision to degrade and destroy ISIS has been made, so the most important goal has to be to frighten ISIS. I don’t want U.S. combat troops in the fight against ISIS—this is the responsibility of Arabs and Kurds. But I do want the leaders of ISIS to believe that Obama is capable of waging all-out war against them.

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