The change, announced Wednesday by Defense Secretary Robert Gates, is the latest blow to an all-volunteer Army that has been given ever-shorter periods of rest and retraining at home between overseas deployments.
Rather than continue to shrink the at-home intervals to a point that might compromise soldiers' preparedness for combat, Gates chose to lengthen combat tours to buy time for units newly returned from battle.
"Our forces are stretched, there's no question about that," Gates said.
The extended tours are a price the Army must pay to sustain the troop buildup that President Bush ordered in January as part of his re-jiggered strategy for stabilizing Baghdad and averting a U.S. defeat. Troop levels are being boosted from 15 brigades to 20 brigades, and in order to keep that up beyond summer the Army faced harsh choices: either send units to Iraq with less than 12 months at home, or extend tours.
Reaction on Capitol Hill to Gates' announcement was harsh.
Rep. Ike Skelton, D-Mo., chairman of the House Armed Services Committee, said the longer tours will have a "chilling effect" on recruiting and the Army's ability to keep soldiers from quitting the service.
"We also must not underestimate the enormous negative impact this will have on Army families," Skelton said.
Sen. Chuck Hagel of Nebraska, one of only two Republicans who voted to set a timetable for beginning to withdraw troops from Iraq, said Gates' announcement was a "stark admission that the administration's policies in Iraq are doing permanent damage to our military."
Sen. Lindsey Graham, R-S.C., who supports the troop buildup, said of the affected soldiers, "They'll be disappointed, but they'll do it."
Indeed, at Fort Hood, Texas, home of the 4th Infantry Division, some Army families took the news in stride.
Carol Frennier, whose husband, Command Sgt. Maj. Steve Frennier, is in Iraq, said she had prepared herself and her family for a longer deployment.
"They kind of told us to expect 12 months to 18 months," she said. "We were already prepared to have them extended." And her family has been through an extended tour of duty before.
"Last time they said nine months, and it was 14 months," Frennier said.
It's not just soldiers that are in short supply, reports CBS News national security correspondent David Martin. The White House is having a hard time finding a retired general to become a new czar to coordinate war strategy for both Iraq and Afghanistan.
At least five retired generals have said "no," Martin reports, some citing personal reasons. But one of them, Retired Marine Jack Sheehan, said he turned it down because "I don't think they've got a coherent strategy."