The war in Afghanistan -- the United States' longest -- has cost taxpayers at least $19 billion over the past decade.
Public opposition to the war has declined from its record in December, likely influenced by the killing of Osama bin Laden, but it remains high.
In an ABC News/Washington Post poll published earlier this month, 54 percent of Americans said the war had not been worth fighting, and 73 percent said the United States should withdraw a substantial number of U.S. combat forces from Afghanistan this summer.
The poll, however, found that Republicans are more apt than others to say the war has been worth fighting. Fifty-three percent of Republicans polled said it was worth the cost and effort and 67 percent felt it contributed to long-term security. A majority -- 59 percent of Republicans -- support a major withdrawal, which is set to begin next month.