President Barack Obama. (POOL/REUTERS)
Opinion writer

President Obama’s foreign policy has been a regular punching bag for Republican presidential candidates, but many of their criticisms are facile. The next president — from whichever party — will have to confront the same puzzle that Obama has faced about how best to use U.S. power in a world that resists military solutions.

Republican denunciations of Obama avoid the deeper problems: Where should the United States intervene, and at what cost? How should the rise of Chinese power be managed? What’s the right response to the pugnacious Russian autocrat Vladimir Putin? It’s easy to argue for American engagement, but what does that mean in failed states such as Syria, Libya and Yemen?

GOP candidates have the luxury, in debate sound bites, of criticizing Obama’s weakness without specifying what they would do differently. They want to project American power more aggressively, but few argue for sending more troops. A default criticism is that Obama lacks a strategy. That may be true in some instances, but as Ryan Lizza noted recently in the New Yorker, it’s a charge that “politicians revert to whenever they want to avoid details.”

What’s the real agenda for the next president? Derek Chollet, a former assistant secretary of defense, argues that the United States should pursue what he calls “The Long Game” in a forthcoming book with that title. By this, he means a political-military strategy that’s balanced and sustainable — one that fits U.S. commitments with available resources and doesn’t promise more than it can deliver.

Graham Allison, director of the Belfer Center at the Harvard Kennedy School, makes a similar point in the National Interest: “The survival and success of the United States as a free nation is the essential prerequisite for America’s power being applied to achieve any larger objectives in the world.” That’s a caution that U.S. commitments should be limited by our economic capacity and national interests.

Obama’s presidency has been a wager that we live in a rational world where other major powers will follow their interests, too. That’s certainly the premise of Secretary of State John F. Kerry’s nuclear deal with Iran and his new attempt to start a peace process in Syria. He’s betting that Russia, Iran, Saudi Arabia and Turkey will eventually seek a political settlement of the Syrian civil war that has been ruinous for all.

Kerry is attempting a step-by-step de-escalation in Syria. This weekend in Vienna, he will try to get other leaders to agree on the common enemy — presumably, the Islamic State and al-Qaeda affiliate Jabhat al-Nusra — and then begin a process that can gradually bring the rest of the opposition into discussion with the Syrian regime about a political transition. It’s an eminently sensible approach to a conflict that has no military solution, but it doesn’t address the sectarian rage that’s driving the conflict.

Obama knows his belief in rationality is hard to square with human history. As he said in his 2009 Nobel Peace Prize address, “Make no mistake: Evil does exist in the world. A nonviolent movement could not have halted Hitler’s armies. Negotiations cannot convince al-Qaeda’s leaders to lay down their arms. To say that force may sometimes be necessary . . . is a recognition of history; the imperfections of man and the limits of reason.”

Philip Hammond, the British foreign secretary, makes the case for assuming rationality in dealing with Iran, Russia and other hard-line regimes. “Iran, as it engages in the region, will have reasons to moderate its behavior. It will have a stake in the game,” he said Tuesday at The Post.

But Hammond also offered this caveat: Nations are sometimes driven by the ambition and dexterity of their leaders. Russian President Putin “likes to throw a rock in the water and see what happens.” He “dials power up and down,” exploring options he may not use, but “the one thing that Putin will never tolerate is to be seen as looking weak,” Hammond cautioned.

Obama sometimes seems overmatched in a world of power players such as Putin and Chinese President Xi Jinping. But in his foreign policy, Obama has been experimenting with the hard questions: How does the United States calibrate its power to the realities of the world, after its unsuccessful invasions of Iraq and Afghanistan? How does it work with other nations to address an Islamic extremism that can destabilize the entire world if left unchecked?

Obama has sometimes fired blanks in his foreign policy. But he’s shooting at the right target.

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