Primary concern: Mission creep

President Barack Obama is adamant that the war against the Islamic State will not escalate to the use of U.S. ground troops. But the more I see and hear of his strategy, the more I fear that “mission creep” - even if the president resists it - is baked in from the start.

Gen. Martin Dempsey, the chairman of the Joint Chiefs of Staff, was jarringly candid Tuesday when he told the Senate Armed Services Committee that the administration’s plan of marshaling an international coalition, with U.S. air power supporting the Iraqi army and moderate Syrian rebels, is “the appropriate way forward.”

Dempsey said he believes his optimistic view “will prove true.” But if it does not, “and there are threats to the U.S., then of course I would go back to the president and make the recommendation that may include the use of U.S. military ground forces.”

Dempsey’s words sent administration officials scrambling to reiterate that no deployment of combat forces was being considered - not counting the hundreds of trainers, advisers and intelligence operatives already on the ground and the hundreds more on the way.

Obama sought to settle the question Wednesday with a categorical statement during a visit to U.S. Central Command in Tampa. “As your commander in chief,” he told the assembled troops, “I will not commit you and the rest of our armed forces to fighting another ground war in Iraq.”

That’s as clear a declaration as anyone could want but not terribly reassuring. I have increasing trouble squaring the president’s pledge, which I believe to be sincere, with reality in the chaotic badlands of Iraq and Syria.

Obama’s vow to “degrade and ultimately destroy” the Islamic State means intervening in both the Syrian civil war and the Sunni-Shiite conflict in Iraq. The former is a horror-filled bloodbath; the latter, a centuries-old religious struggle. U.S. airstrikes will inevitably change the course of both conflicts - and not necessarily in ways we would like.

Especially troubling is that by bombing Islamic State installations and assets in Syria, the United States will weaken Syrian dictator Bashar al-Assad’s most capable and dangerous foe.

According to news reports, Assad’s commanders are already taking advantage of this windfall to launch a new offensive against the “moderate” Free Syrian Army rebels - the ones Obama now reluctantly plans to train and arm.

As we have already seen, the Islamic State is vulnerable to U.S. air power. But the jihadist group has more than 30,000 fighters, according to the latest CIA estimate, and is flush with weapons and cash.

No one, including Obama, claims that airstrikes alone can “destroy” the group.

Until recently, the president has been deeply skeptical of the capabilities of the non-jihadist Syrian rebels and the Iraqi army. Now he says he believes these forces, with U.S. training and support, can defeat the Islamic State.

What changed the president’s mind? In Iraq, the formation of a new government may be a positive step, assuming Prime Minister Haider al-Abadi is less of a sectarian bully than his predecessor. In Syria, however, there has been no development I know of that makes U.S. involvement a more attractive prospect.

Hawks on Capitol Hill who are pushing Obama to be more aggressive in using military force must not be paying attention. Obama has already specified a maximalist goal - basically, wiping the Islamic State off the map - and an open-ended time frame. If eliminating what some commentators have called “Jihadistan” is a core U.S. national interest, failure is not an option.

Dempsey was addressing a perfectly reasonable question, one that Obama avoids: What if this carefully calibrated application of U.S. military power doesn’t work? He gave the answer that would be expected from a professional soldier, which is that if limited force is ineffective at achieving a vital goal, greater force should be applied.

I cannot avoid concluding that the logic of Obama’s strategy points toward escalation. If that’s not true, I wish he would explain why.

Eugene Robinson is a columnist for the Washington Post.