WASHINGTON (CNN) -- President Bush on Tuesday announced a troop deployment shift for America's two wars, a move that reflects a more stable Iraq and an increasingly volatile Afghanistan. President Bush said Tuesday that he soon will start bringing some U.S. troops home from Iraq. Through early next year, about 8,000 American troops will leave Iraq and not be replaced. Some 4,500 other U.S. service members will go to Afghanistan. Bush also emphasized the U.S. intention to help Pakistan defeat insurgents who are using the country's tribal areas to stage attacks in Afghanistan. "Iraq, Afghanistan and parts of Pakistan pose unique challenges for our country," Bush said Tuesday in a speech at the National Defense University in Washington. "Yet they are all theaters in the same overall struggle."
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NEW: Sen. Barack Obama, House Armed Services chairman criticize scope, timing
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NEW: Iraq views decision as "positive move," aide to Iraqi leader says
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Iraq force to be trimmed by 8,000; Afghanistan force to rise by 4,500
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President Bush cites increased stability in Iraq, stronger insurgency in Afghanistan
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"More significant troop reductions in Iraq are needed so that we can start to rebuild U.S. military readiness and provide the additional forces needed to finish the fight in @placeholder."
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Skelton said Iraq "cannot continue to overshadow other critical @placeholder security needs."
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"The effort in @placeholder must move to the forefront and once again become our top priority," he said.
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Bush said stepped-up insurgent efforts in @placeholder have necessitated the increase of U.S. troops from "less than 21,000 two years ago to nearly 31,000 today."
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Bush described challenges in @placeholder that don't exist in Iraq.