[cnn-photo-caption image= http://i.l.cnn.net/cnn/2008/POLITICS/03/19/bush.iraq/art.bush.ap.jpg caption=" President Bush tours the Blount Island Marine Terminal on Tuesday in Jacksonville, Florida."](CNN) - President Bush will mark the fifth anniversary of the Iraq war on Wednesday by calling the debate over the conflict "understandable" but insisting that a continued U.S. presence there is crucial.
"The answers are clear to me," Bush will say, according to excerpts of his speech to be delivered at the Pentagon on Wednesday, the day the war began in 2003.
"Removing Saddam Hussein from power was the right decision, and this is a fight America can and must win."
Almost 4,000 American troops have died in the war, a painful toll that Bush will acknowledge.
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