Speaking on August 31 to the American people from the Oval Office, President Barack Obama announced that the U.S. combat mission in Iraq was over after more than seven costly years. "Now, it's time to turn the page," he said. But turning the page entirely will be difficult; in fact, the president raised more questions than he answered.

The fifty thousand U.S. troops still in Iraq are there to advise and assist. But what happens if Iraqis cannot deal successfully with the continuing threat posed by terrorists, their own sectarian divides, and the meddling of neighbors? What is the continuing U.S. stake in Iraq, and what is the United States prepared to do on its behalf?

What is more, the president reiterated his commitment to ending the U.S. military presence in Iraq entirely by the end of 2011. But would this be wise? Doing so would increase the odds that Iraq would become far messier. Iraqis themselves realize this, and if and when a new government is formed, its leaders are likely to ask that tens of thousands of American troops stay on for an extended period. There is a strong case that the United States should be prepared to do so; Iraqis should be prepared not only to ask for this but to help pay for it.

The president suggested that Iraq was something of a precedent for Afghanistan, in that a military build-up could buy time to train government forces so they could assume a larger role, thereby allowing for a drawdown in American troop numbers and activity. "Open-ended war serves neither our interests nor the Afghan people's," Obama declared. But the calendar-vs.-conditions contradiction at the heart of U.S. Afghan policy remains: U.S. troops will begin to depart in less than a year, but the pace of withdrawals will be determined by the situation on the ground.

What if conditions in Afghanistan do not improve at a pace to allow meaningful troop withdrawals? This is all too possible given the divided and corrupt Afghan central government, a Pakistani "partner" that is pursuing its own agenda, and a resilient Taliban. The time will come, hopefully sooner than later, when the president will reject both a calendar and a conditions-based approach to Afghanistan and adopt a less ambitious and costly goal of going after terrorists, establishing local partnerships, and reaching an accommodation with those Taliban leaders willing to distance themselves from al-Qaeda.

Considerations of cost are significant here, as the president also stated that "our most urgent task is to restore our economy." This may well be true, but spending $100 billion or more a year in Afghanistan will make the process of cutting defense spending and reducing the deficit far more difficult. How, then, should the United States manage its need to restore its fiscal base and remain the world's leading power? This may be the biggest question of all, one that we look forward to the president and the congressional leadership addressing.

Richard N. Haass is president of the Council on Foreign Relations and the author of "War of Necessity, War of Choice: A Memoir of Two Iraq Wars"

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