The List: The Final Four

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John McCain

What hes running on: The Long War

Best idea: The surge. When he says he supported it all alonghe did. When he says its workingit is. Violence in Iraq is down by more than half, and three quarters of Baghdads neighborhoods are now secure. Such gains are fragile and political reconciliation remains elusive. But whether it was experience, foresight, or luck, McCain had it mostly right on this issue.

Worst idea: Staying 100 years in Iraq. Baghdad is a far cry from Heidelberg or Seoul. Whether or not the United States is still taking casualties in 2009, it wont be long before U.S. troops overstay their welcome.

Where the heck is he on … North Korea? In 2000, the Arizona senatora fiery critic of Bill Clintons diplomatic approach to Pyongyangwas calling for the rollback of the North Korean regime. But he has been awfully quiet about the Bush administrations remarkably Clintonian nuclear bargaining, and devoted just 70 words to North Korea in a recent 5,305-word opus in Foreign Affairs.

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Mitt Romney

What hes running on: Synergy

Best idea: Reagan Zone of Economic Freedom. The name is a clumsy attempt to don the Reagan mantle, but Romneys call to include the European Union in a free-trade area is intriguing. Together, the United States and Europe make up roughly 60 percent of the worlds GDP. If the Doha round of trade talks fails to produce a global agreement, a trans-Atlantic free-trade zone might make a good Plan B.

Worst idea: Double Gitmo. Romney says he wants to double Guantnamo. Even President George W. Bush acknowledges the controversial detention facility has hurt the United States international image and says he wants to close it. But Romney would rather double down.

Where the heck is he on … political reform in the Middle East? Romneys new Middle East advisor is Liz Cheney, the vice presidents daughter and the former point woman for Bushs freedom agenda in the region. But when Romney touts his plans for confronting radical jihad, he rarely mentions democracy or elections, focusing instead on trade, economic development, and the rule of law. Some experts argue for just such a policy shift, but bringing in the architect of Bushs regional democracy-promotion efforts signals muddled thinking on this issue.

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Hillary Clinton

What shes running on: 90s nostalgia

Best idea: The return of etiquette. Failing to observe the niceties of diplomacy has been a hallmark of the Bush era. Clinton says she would seize the moment of opportunity to restore Americas global standing and reconnect with allies miffed by Bushs ham-handed approach.

Worst idea: The Third Way on Iraq. On the campaign trail, Clinton calls for bringing the troops home. She nonetheless intends to maintain a residual force that will battle al Qaeda and deter Iran, but no longer provide security in Iraqi neighborhoods. Her plan, she claims, will stabilize Iraq as our forces withdraw. Counterinsurgency experts warn, however, that sustained, intensive involvement is the only way to defeat entrenched guerillas. Sandwiched between her centrist impulses and stinging criticism from war opponents, Clinton risks settling on a middling approach: just enough troops to lose.

Where the heck is she on … trade? Clinton is savvy enough to know how the global economy really works, but the primary has led her to toe the union line. Her husband fought hard to pass the North American Free Trade Agreement (NAFTA); Hillary now criticizes it. Asked if she supports free trade, the senator demurs, saying, I want to be a smart, pro-American trader. She opposed the Central American Free Trade Agreement (CAFTA) and the U.S.-South Korea deal, and has proposed reevaluating U.S. trade agreements every five years.

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Barack Obama

What hes running on: Himself

Best idea: Never fearing to negotiate. As the worlds overwhelming superpower, the United States has little to lose by sitting down with its far weaker enemies. Even Ronald Reagan, as the Illinois senator often points out, cut deals with the evil empire. The odds of success may be small, but failure is certain if America continues to handcuff one of its best weapons: its diplomats.

Worst idea: Invading Pakistan. Seeking to shore up his credibility as a commander in chief, Obama said that he would strike terrorist targets in Pakistan with or without permission from Pakistani President Pervez Musharraf. Technically, Obama never said he would invade Pakistan, but taking out al Qaeda might require a significant incursion of U.S. Special Forcesinvasion by another name. With Musharraf already in domestic political trouble, such a show of U.S. force on Pakistani soil could be the last straw for the Pakistani president. Obama had better realize there is no Thomas Jefferson waiting in the wings.

Where the heck is he on … the use of force? Obama says he will not hesitate to use force, unilaterally if necessary, to protect the American people or our vital interests whenever we are attacked or imminently threatened and would consider using military force in circumstances beyond self-defense. But which of Obamas advisors will have his ear in a crisis: Samantha Power or Richard Clarke? The former beats the drums for humanitarian intervention, and the latter, in Powers own words, was a bystander to genocide in Rwanda.

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