Peter Beinart, editor of OpenZion.com at the Daily Beast, is author of The Crisis of Zionism.

In signaling that he’s likely to select Chuck Hagel as his secretary of defense, Barack Obama is sending a message about his second term. In the decade since 9/11, the spirit of Harry Truman has dominated American foreign policy. Now it may be giving way to the spirit of Dwight Eisenhower. And that could make all the difference in the world.

Truman’s foreign policy was grand. In March 1947, in his speech to Congress requesting aid to Greece and Turkey, and then, more comprehensively, in a secret 1950 strategy paper entitled NSC 68, Truman committed the United States to containing communism everywhere on earth. It was a stirring cause, and hubristic beyond words. The United States lacked the money and manpower, not to mention the wisdom, to ensure that no new nation embraced communism (itself an ill-defined term). And by making global containment the centerpiece of American foreign policy, Truman set America on the path to Vietnam.

George W. Bush, who had avoided his own rendezvous with Vietnam, loved the bigness of Truman’s vision, and set out to emulate it. Thus was born the "war on terror": a vow to use force, or the threat of force, to prevent any new adversary from acquiring nuclear weapons and, ultimately, to transform dictatorships into democracies and foes into clients. That limitless quest has led the United States into unwinnable wars in Afghanistan and Iraq, and threatens to bring us into a third, in Iran. And like Vietnam, it has helped bring us to the brink of insolvency as well.

Barack Obama knows this. But fearful of the Bush-era right, he has failed to break decisively with the hubris he inherited...