Washington ? The inescapable foreign-policy issue for U.S. presidential candidates this year is whether American power is declining and, if so, what to do about it. This strategic conundrum lies behind every challenge the U.S. faces, from Egypt to Afghanistan to China.

For your election-year reading table, I recommend three new books that tee up this question of American power and offer different conclusions. If candidates could honestly debate the issues raised in these books, maybe we could get beyond the slogan-filled evocations of the past — the idealized “shining city on the hill” — and frame policies that fit the real world.

My book-club selections are “The World America Made,” by Robert Kagan of the Brookings Institution; “Liberal Leviathan,” by John Ikenberry of Princeton; and “No One’s World,” by Charles Kupchan of Georgetown.

These are serious, scholarly books, but they go to questions that every voter can understand: Is America’s position in the world eroding? Can the U.S. bounce back, and what’s the right recovery strategy? Or is the liberal international order we’ve known since 1945 giving way to something different and disorderly, no matter what we do?

In this trilateral debate, each of the analysts starts with a recognition that the easy days of unchallenged American power are over. But what comes next?

Kagan argues there’s no good alternative to American leadership, and that we shouldn’t commit “pre-emptive superpower suicide” by acceding to demands from rising nations such as China. He opens with an interesting thought experiment in which he asks the reader to imagine, much like the character George Bailey in the classic movie “It’s a Wonderful Life,” what the world would look like if American power weren’t around.

Kagan’s answer is that things would be much worse without us; the liberal order can’t survive without U.S. power, hard and soft. “If American power declines, this world order will decline with it,” Kagan writes. “It will be replaced by some other kind of order, reflecting the desires and the qualities of other world powers. Or perhaps it will simply collapse.”

Kagan’s message is similar to arguments made by Republican front-runner Mitt Romney. But his book is also much discussed at the Obama White House, though I think the administration’s policies have focused more on adapting American power to a changing world than rebuilding the old primacy.

Ikenberry argues that the global order is more durable and stable than Kagan fears. It’s a genuinely multilateral structure, he contends, and its strength derives from the network of institutions the U.S. helped create after 1945, such as the United Nations, the World Bank, and NATO. America is strong when it operates through this deep structure of power, which has spread our basic values of capitalism and democracy to nearly every corner of the world.

The U.S. may stumble, says Ikenberry, but the rising powers will also be members of the same global order. A group photo is the World Economic Forum at Davos, where newly wealthy Chinese and Indians walk alongside their American and European counterparts. America will stay strong, Ikenberry contends, if it maintains a network of alliances and partnerships and doesn’t try to go it alone.

Obama appears to share Ikenberry’s basic analysis of the multipolar world, though he has also been willing to use American power unilaterally, a la Kagan. GOP candidates such as Romney instinctively mistrust anything with the prefix “multi.”

For a more pessimistic account, turn to Kupchan’s aptly titled “No One’s World.” He argues that the world is beginning what he calls “a global turn,” and that it’s “wishful thinking” to expect it will be congenial to the U.S. and its Western allies. The problem is that Chinese, Iranian, Turkish and Russian models of the future don’t look like ours.

“The world is barreling toward not just multipolarity, but also multiple versions of modernity,” he says. Even if democracy spreads, as seems to be happening in the Arab Spring, “the new regimes that emerge will not necessarily play by the West’s rules just because they are democratic.” Kupchan argues that America’s best strategy for coping is to recover its own domestic political and economic strength — and “not insist that the rising rest acquiesce to Western values and institutions.”

These are big ideas, but they’re expressed clearly and concisely in these three books — which are not the political science door-stoppers we remember from college. I hope Kagan, Ikenberry and Kupchan will stimulate the honest political debate America needs about how best to use its power.