Was the war worth it?

Through the progression of time, the general American's attitude to the war has changed. . Reading an article on msnbc.com (http://www.msnbc.msn.com/id/7730556/), I was able to see through polling, the overall change in attitude toward war with Iraq. In April of 2003, 73% of our population thought that the war was worth fighting. Years later, in February of 2005, that percentage dropped considerably to 48% followed by another recent drop to 41% of our current population thinking the war was worth fighting. This poll is said to have a 5% margin of error. While I do not argue that there has been a change in American attitude over the past two years, I do however question whether the numbers are factual despite the low margin of error. In this example, I feel statisticians run into the same problems they would when taking an exit poll with presidential candidacy. An excerpt at the bottom of this article indicates that a telephone poll of 1,006 adults was conducted. I ask myself what sector of the American public would be susceptible to responding to telephone polls, and whether that correlates with the entire population and their views?