That is why I advocate a phased redeployment of U.S. troops out of Iraq to begin no later than May first with the goal of removing all combat forces from Iraq by March 2008.
In a civil war where no military solution exists, this redeployment remains our best leverage to pressure the Iraqi government to achieve the political settlement between its warring factions that can slow the bloodshed and promote stability.
My plan also allows for a limited number of U.S. troops to remain and prevent Iraq from becoming a haven for international terrorism and reduce the risk of all-out chaos.
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But what is a limited number ?
What kind of forces ?
What kind of situations should US forces engage ?
How long should they be there ?
http://usliberals.about.com/od/extraordinaryspeeches/a/ObamaIsrael_2.htm