Larry Downing / REUTERS U.S. President Barack Obama makes a point at the National Defense University at Fort McNair in Washington, D.C., on May 23, 2013.

In his broad address on drone strikes, al Qaeda terrorists, and the prison at Guantanamo Bay Thursday, Barack Obama wrestled with some of the hardest moral questions that have defined national security policy since September 11: Who is the enemy? Who can we kill, and where, and how? What to do with suspected terrorists we hold in captivity? And when, if ever, will this war as we know it end? Along the way, Obama issued a strong defense of his reliance on drones to kill suspected terrorists in places where other military means are infeasible or risk more civilian deaths. He announced higher standards for drone strikes, limiting them to situations where the confidence about a target’s location is extremely high and the possibility of civilian casualties is virtually nil. He reiterated his belief that the Guantanamo prison is a stain on America’s honor and image around the world and should be closed, and vowed new action to make that long-delayed goal a reality.

(VIDEO: Obama Press Conference April 30, 2013)

But while Obama has an obviously sincere desire to bring the war against al Qaeda to a close and close the books on Guantanamo, however, he also lacks the power to make these things happen on his own. The future of the terror war that Obama inherited from George W. Bush and Dick Cheney depends on some very open questions:

Will Republicans Play Along? The initial GOP response to Obama’s speech was skeptical. “The theme of the speech was that this war is winding down… [but] the enemy is morphing and spreading, there are more theaters of conflict today than in several years,” said GOP Senator Lindsey Graham of South Carolina. “The President’s speech today will be viewed by terrorists as a victory,” declared Saxby Chambliss of Georgia.

Some of Obama’s plans require no Republican sign-off—he can change the rules governing drone strikes, for instance, by presidential directive. And he can transfer the dozens of Yemeni detainees at the camp who have been cleared for release back to their home country on his own. But fully shuttering Gitmo will require him to win Congress’s permission to move dozens of the camp’s 166 inmates from Cuba into the U.S., something now barred by law. At the moment, some Republicans seem no more interested in helping him than they did when Obama first proposed this idea in 2009. “GITMO must stay open for business,” Chambliss said Thursday. Others are more amenable, though still skeptical: House Armed Services Chairman Buck McKeon, who would play a lead role in any Congressional action, calls himself “open to a proposal from the president, but that plan has to consist of more than political talking points.”

(MORE: President Obama Sides With His Guantanamo Bay Protesters)

Obama also said that he wants Congress to revisit the Authorization for Use of Military Force, the law it passed a few days after the September 11 attacks authorizing the broad use of force to fight al Qaeda and its allies; the president suggested he might like to see the law repealed eventually. Many Republicans like it just fine, and would oppose efforts to limit its scope.

Will al Qaeda Regain its Strength? Obama’s speech described a more limited al Qaeda threat that the kind of mass-casualty attack within America that changed history on September 11, 2001. He described al Qaeda’s leadership in Pakistan as decimated, and said that small-scale attacks from domestic radicals, like the Tsnaraev brothers, or attacks on American targets abroad, like the U.S. compound at Benghazi, are the likely new norm. There’s no question that those threats are real. But intelligence officials say that at least one al Qaeda affiliate—the group’s Yemen branch—still poses a dangerous threat to the United States. And although al Qaeda may be on the run in some places, it is also gaining strength in others, like northern Africa, Iraq, and Syria, where the prospect of al Qaeda-affiliated radicals acquiring chemical weapons is real. On Thursday an administration official noted in a briefing for reporters that unrest of the Arab Spring has allowed anti-American radicals to “gain a foothold” in new places. It’s possible that self-proclaimed al Qaeda terrorists in those areas will maintain regional ambitions. But it’s also possible they will renew their efforts to strike at America, perhaps compelling Obama to step up his use of drones.

(MORE: What if al Qaeda Gets Syrian Chemical Weapons?)

Is Closing Guantanamo Good Enough? There are two major cases against Guantanamo. The first is that the camp itself damages our national security by inspiring anti-American sentiment and serving as a rallying cry for jihadists. By this thinking, shutting down the facility is a huge breakthrough. And it may be.

But there’s another other critique. This one holds that Guantanamo itself isn’t the problem. It’s the policy behind it: indefinite detention. Obama’s plan would send some Guantanamo detainees back to their home in Yemen, and possibly to some other countries, and try others in the criminal and military justice systems on U.S. soil. But even Obama’s plan would leave nearly 50 prisoners in a state of indefinite detention. These are prisoners who probably can never be charged in court, either because the evidence against them is tainted by the use of torture, or because the government is convinced they are dangerous but does not have specific charges to mount against them. On this question, Obama essentially punted: “[O]nce we commit to a process of closing GTMO, I am confident that this legacy problem can be resolved, consistent with our commitment to the rule of law,” he said.

“[H]istory will cast a harsh judgment on this aspect of our fight against terrorism, and those of us who fail to end it,” Obama went on to say. But he has not offered a clear plan for what to do with these prisoners who apparently cannot be tried. One thing he does not seem prepared to do is simply release them. America may have damaged al Qaeda enough that Barack Obama can talk about a day when the war against the disciples of Osama bin Laden will be over. But that day has not yet arrived. And until it does, Obama may have to live with some unpleasant moral compromises.

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