There’s an air of tragedy about President Obama. He wants to chart a new course—pivot to the Pacific, end the long decade of war, do nation-building at home—but the old world’s most derelict, dysfunctional quarters keep pulling him back in. Now, in the cruelest irony, the gusts are pulling him back to the very land where he least wants to set foot again, the warzone that he spent most of his first term leaving: Iraq.

“We will not get dragged into another ground war in Iraq,” he insisted in his televised speech Wednesday night. Instead, this will be a war where others—mainly Iraqi soldiers—fight on the ground, while American advisers devise the battle plans and American pilots pummel the enemy with missiles and bombs.

Still, one could be excused for feeling a spasm of dread as the speech spilled forth. I wouldn’t be surprised if the president himself heaved a sigh while he wrote it.

That said, the policy that he outlined—his strategy to “degrade and ultimately destroy” the terrorist group known as ISIS—is as reasonable, and has as much chance of succeeding, as any that might be conceived.

There are two big new elements in this policy: First, air strikes will no longer be restricted to areas where ISIS poses a threat to U.S. personnel. Instead, they can strafe and bomb ISIS targets anywhere in Iraq, coordinating the strikes with assaults on the ground by Iraqi soldiers, militias, or Kurdish peshmerga.

Second, these air strikes will take out ISIS jihadists not only in Iraq but also across the border in Syria. A senior official stressed that this part of the policy is not as open-ended as the speech makes it seem. Obama is well aware that air strikes alone don’t produce victory. They need to be synchronized with ground assaults. And for now, there are no ground forces in Syria that can beat back ISIS.

So, at least initially, U.S. air strikes in Syria will be clustered along the Iraqi border, to keep ISIS jihadists from moving back and forth between the countries or from seeking safe haven—in much the same way that drones were fired at northwest Pakistan to deny safe haven to Taliban who’d been fighting in Afghanistan.

However, these air strikes will eventually expand across Syria. Another part of Obama’s strategy (and he did outline this in his speech) is to train and equip the Free Syrian Army, the more moderate militiamen currently being squeezed both by ISIS and Syrian President Bashar al-Assad. (They’ll be trained by special forces on a base in Saudi Arabia.) Once they’re trained and armed, the FSA will return to Syria and—with the help of U.S. air strikes—take back their own territory from ISIS.

Obama’s plan also calls for a wide coalition of European, Arab, and Muslim countries to join the fight. ISIS is an extremist Sunni movement, so it’s especially vital to get predominantly Sunni nations involved—to demonstrate that this is not an American war or a sectarian war of Sunnis versus Shiites. (For this reason, Obama is loath to bring Iran or Assad’s Syria—both Shiite regimes—into the alliance. They too deeply hate ISIS, but the Saudis and other Sunni leaders might not enter the fight if it looks like they’re supporting Iran. What arrangements are made with Iran or Syria behind the scenes is another matter.)

Obama, never prone to hype, made clear in his speech that the ISIS jihadists don’t yet pose as big a threat as al-Qaida did 13 years ago, on the eve of the World Trade Center attacks. But they are on a rampage, amassing fortunes, acquiring arsenals, led by competent commanders (many of them Saddam Hussein’s former generals), playing on anti-Shiite (and anti-Western) sentiment among Sunni radicals. If they are allowed to take over Iraq and Syria, it’s fair to ask if Jordan and Saudi Arabia might be next. They are also recruiting European jihadists, who have passports that let them travel across the continent and into the United States. Clearly, they do pose a threat. This cannot and should not be principally America’s fight; but the fact is, America is the only country that can coordinate the coalition—provide the intelligence, logistics, and accurate air strikes—needed to win.

So, the cause is just, and Obama’s plan sounds reasonable, even nuanced. What could go wrong? Well, as anyone who’s studied the region (and the cavalier predictions made, time and again, by Westerners who go to war there), everything.

Obama made very clear that this battle requires active participation by the Saudis, Turks, and Europeans. But the roles and missions haven’t yet been outlined; the commitments aren’t quite carved in concrete. The plan has a chance of succeeding in Iraq because the new government, formed by Haider al-Abadi, seems inclusive, embraced by Sunnis and Shiites, for the moment—but it could fall apart with the bombing of a single mosque or a marketplace, and then what? Will it look like the Americans are advising and bombing on behalf of a Shiite regime? Will the other Sunni nations back away, fearing the association?

As for Syria, the endgame is unclear. If the Free Syrian Army can’t get its act together, despite all efforts, will Obama step back from that terrain and focus again on Iraq—or will he be tempted to escalate and take on more of the fight alone from the air? Obama is allergic to “mission creep” (and that’s good), but he has said that this war will go on for a while; his advisers were recently quoted as saying at least three years. Where will the next president take the fight? To draw a Vietnam analogy (which, granted, should not be stretched too far), will he or she be Lyndon B. Johnson to Obama’s John F. Kennedy? (JFK sent only advisers to Vietnam, refusing to deploy combat forces.)

Meanwhile, Obama is doing as close to the right thing as the mess of the Middle East allows. And maybe he’ll pull it off. But all tragedy is enmeshed with noble causes and good intentions; it wouldn’t be tragedy without them—it would only be farce. This battle is not a farce. It will take massive political effort, delicate diplomacy, and enormous luck to ward off tragedy. It’s worth a try.