Facing a war-weary public, President Obama is expected to call for a major withdrawal of American troops from Afghanistan tonight, with roughly 10,000 coming home to the United States in less than a year.
The phased drawdown is likely to start with 5,000 troops recalled this summer and an additional 5,000 by winter or spring 2012, according to a senior U.S. defense official.
Obama is also weighing a timetable for bringing home the 20,000 other troops he ordered to Afghanistan as part of a surge -- his December 2009 decision to send reinforcements to reverse the Taliban's battlefield momentum.
The withdrawals would put the United States on a path toward giving Afghans control of their security by 2014 and ultimately shifting the U.S. military from a combat role to a mission focused on training and supporting Afghan forces.
Obama is to address the nation from the White House at 8 p.m.
The president reached his decision a week after receiving a range of options from Gen. David Petraeus, the top U.S. and NATO commander in Afghanistan. Obama informed his senior national security advisers, including Secretary of State Hillary Rodham Clinton and outgoing Defense Secretary Robert M. Gates, of his plans during a White House meeting Tuesday.
"The president is commander in chief," said spokesman Jay Carney. "He is in charge of this process, and he makes the decision."
The Obama administration has said its goal in continuing the Afghan war, now in its 10th year, is to blunt the Taliban insurgency and dismantle and defeat al-Qaida, the terror network that used Afghanistan as a training ground for the Sept. 11, 2001, attacks.
As of Tuesday, at least 1,522 members of the U.S. military had died in Afghanistan as a result of the U.S. invasion of the country in late 2001, according to an Associated Press count.
Roughly 100,000 U.S. troops are in the country, three times as many as when Obama took office. Even by drawing down the 30,000 surge forces, there will still be great uncertainty about how long the remaining 70,000 troops would stay there, although the United States and its allies have set Dec. 31, 2014, as a target date for ending the combat mission in Afghanistan.
A reduction this year totaling 10,000 troops would be the rough equivalent of two brigades, which are the main building blocks of an Army division. It's not clear whether Obama's decision would require the Pentagon to pull out two full brigades or, instead, a collection of smaller combat and support units with an equivalent number of troops.
If Obama were to leave the bulk of the 30,000 surge contingent in Afghanistan through 2012, he would be giving the military another fighting season -- in addition to the one now under way -- to further damage Taliban forces before a larger withdrawal got started. It also would buy more time for the Afghan army and police to grow in numbers and capability.
Under that scenario, the emphasis in U.S.-led military operations is likely to shift away from troop-intensive counterinsurgency operations toward more narrowly focused counterterrorism operations, which focus on capturing and killing insurgents.
Afghan security forces and judicial institutions are expected to take up many aspects of the counterinsurgency fight by establishing the rule of law and respect for government institutions, U.S. officials in Afghanistan said Tuesday.
In recent speeches, Afghan President Hamid Karzai has criticized American forces, suggesting his ally is in danger of becoming an occupying force. He has even threatened action against international forces that conduct air strikes and has accused allies of undermining and corrupting his government.
Obama has previously said he favors a "significant" withdrawal beginning in July, his self-imposed deadline for starting to bring U.S. troops home. Aides, however, have never quantified that statement.
Pressure for a substantial withdrawal has been mounting from the public and Congress. Even Gates, who has said he favored a "modest" withdrawal, said Tuesday that Obama's decision needed to incorporate domestic concerns about the war.
According to an Associated Press-GfK poll last month, 80 percent of Americans say they approve of Obama's decision to begin withdrawal of combat troops in July and end U.S. combat operations in Afghanistan by 2014. Just 15 percent disapprove.
Following the announcement on the drawdown, Obama will visit troops Thursday at Fort Drum, the upstate New York Army post that is home to the 10th Mountain Division, one of the divisions most frequently deployed to Afghanistan.