NATO leaders on Monday adopted President Obama's exit strategy from the nearly 11-year-old U.S.-led intervention in Afghanistan, cementing an "irreversible" pullout of foreign combat troops that will leave Afghan security forces with the leading role in combat operations by summer 2013.
"We are now unified to responsibly wind down the war in Afghanistan," Obama declared at a news conference at the close of the two-day summit in his hometown, while acknowledging that serious risks persist. "Afghans can take responsibility for their own country so our troops can come home."
The exit plan leaves Afghanistan facing grave uncertainties: Can its forces take over the main fight against the Taliban-led insurgency and avert a resurgence of the mayhem that raged before the 2001 U.S.-led invasion, allowing al-Qaida to establish a virtual parallel state in the country?
The strategy also means that Afghan President Hamid Karzai's weak government will conduct a 2014 election for his successor as the last U.S. and allied combat forces are leaving, potentially jeopardizing the country's first peaceful transfer of political power.
Obama and the 27 other leaders of the alliance, however, are confronting intense pressure from war-weary publics to bring their troops home and focus on restoring growth and creating jobs amid Europe's intensifying financial crisis and overstretched national budgets.
For Obama, the strategy has required a delicate balancing act in the midst of a re-election fight clouded by a weak U.S. economic recovery: He must bow to the majority of Americans, who oppose the war, while reassuring Karzai and his people that the United States won't abandon them as it did after the 1979-89 Soviet occupation.
"I think it is the appropriate strategy whereby we can achieve a stable Afghanistan that won't be perfect," Obama said. "We can pull back our troops in a responsible way, and we can start rebuilding America and making some of the massive investments we've been making in Afghanistan here back home, putting people back to work, retraining workers, rebuilding our schools."
Responding to concerns that the withdrawal of U.S. combat power may be premature, Obama acknowledged that the Taliban remain "a robust enemy." But he added that he's satisfied with assessments by White House military advisers who served in Afghanistan that the strategy will work.
"I can't afford a whitewash. I can't afford not getting the very best information in order to make good decisions," he said. "The Afghan security forces themselves will not ever be prepared if they don't start taking responsibility" for the country's security.
The U.S. intelligence community, however, has warned that the gains made by the 2010 surge of some 30,000 American troops into the Taliban strongholds of southern Kandahar and Helmand provinces could be lost as those forces are withdrawn at the end of this summer.
NATO's 130,000-strong International Security Assistance Force would support Afghan troops and police until it departs by the end of 2014.
In an escalating election-year environment, Obama was at the center of the action in Chicago, beaming and boasting about the city's performance in hosting the event. Noisy protesters loaded the city's streets at times, which Obama called just the kind of free expression NATO defends.
The summit also was overshadowed by an unresolved dispute over the reopening of NATO supply routes with Pakistan, which closed them in November after U.S. forces in Afghanistan accidentally killed 24 Pakistani troops on their side of the border.
The administration had invited Pakistani President Asif Ali Zardari to the summit in hopes that would help clinch agreement on reopening the corridors from the Pakistani port of Karachi, but differences persisted over how much the United States will pay per container.
Obama refused to meet formally with Zardari, but did, however, have two brief informal chats Monday with his Pakistani counterpart.