To a lot of people, it sounded good at the time. The country was united, the military was triumphant, the mood was resolute. Americans were ready, literally, to take on the world.

Now it sounds crazy. The military is cracking from wartime strain. Isolationism is on the rise. Americans don't want to sustain one pre-emptive war, let alone start others.

And so the Bush Administration has begun cribbing from a very different doctrine: Richard Nixon's. The Nixon Doctrine is the foreign policy equivalent of outsourcing. Nixon unveiled it in 1969 to a nation wearied by Vietnam. No longer would Americans man the front lines against global communism. In Vietnam, we would turn the fighting over to Saigon. In the Persian Gulf, we would build up Iran to check Soviet expansion. America would no longer be a global cop; it would be a global benefactor, quartermaster and coach--helping allies contain communism on their own.

Now President Bush is trying something similar. For much of 2006, Administration officials fretted about Somalia, where some of the ruling Islamists had terrorist ties. Next door in Djibouti, America stations around 1,000 troops. But instead of sending them in, we turned to Ethiopia, Somalia's neighbor and longtime rival. When the Ethiopian military rolled into Mogadishu and sent the Islamists fleeing last week, the Bush Administration kept a low profile, applauding the invasion and thanking its lucky stars that it was Ethiopia that launched it, not us.

It's becoming a familiar story. In Afghanistan, the U.S. has handed over much of the anti-Taliban fight to NATO. On North Korea, America works largely through China. On Darfur, we have banked on peacekeepers from the African Union. This past summer the Bush Administration briefly put Israel in charge of our Iran policy, supporting Jerusalem's war against Hizballah in hopes of crippling Tehran's powerful Lebanese ally. And in Iraq the U.S. is relying more and more on Nouri al-Maliki to defeat the insurgents, disarm the militias and give us a way out.

All this outsourcing makes some sense. Bogged down in Iraq, America simply can't intervene as aggressively--militarily or even diplomatically--as we could a few years ago. But there are costs too. When America relies on other countries to do our bidding, they often end up doing their own instead. Ethiopia may capture some terrorists, but it is also making a play for dominance in Africa's horn. Somali Islamists have already vowed to wage guerrilla war against the country's new occupiers. If Ethiopia tries to make Somalia its puppet, it could spur a nationalist insurgency backed by archrival Eritrea. And that could spark a regional war.

Outsourcing has created problems elsewhere as well. Some of America's NATO partners won't send their troops to Afghanistan's dangerous south. On North Korea, China has put enough pressure on Pyongyang to make it resume talks on its nuclear program but not nearly enough to make those talks go anywhere. Finally, while the Bush Administration cheered on Israel last summer as it destroyed Hizballah encampments from the air, the bombing campaign virtually destroyed Lebanon's pro-Western government as well--wrecking what was once a crown jewel in Bush's campaign for Middle East democracy.

The original Nixon Doctrine didn't turn out that well either. When American troops left, South Vietnam crumbled. The Shah of Iran, America's bulwark against Soviet meddling in the Persian Gulf, used the threat of communist subversion to establish a dictatorship. A few years later, the ayatullahs were in power.

In the short run, we may have little choice but to outsource parts of our foreign policy. But in the longer term, America will pay dearly for its inability to lead. The return of the Nixon Doctrine is one of the hidden costs of the war in Iraq. And it is another reason that, unless Iraq's leaders quickly forge a political compact across sectarian lines, America must leave. When that happens, U.S. policymakers will be able to scan the globe anew, with more time and resources at their command. Then the U.S. can abandon the Nixon Doctrine once and for all.

Beinart is a senior fellow at the Council on Foreign Relations

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