Casey Sheehan joined the Army in 2000, while Clinton was still in office, and before 9/11. There was no war at that time.
And Cindy Sheehan was "devastated" that he joined at that time. She wasn't upset because she was against the Iraq war, she simply didn't want her son joining the military, even when there was no war to be fought.
She opposed her son voluntarily joining the military.
He re-enlisted after the Iraq war's major combat operations ended. I haven't seen a date for his re-enlistment.
Casey's views and her views have never changed. She's always been a anti-war nut, while her son died for the freedom of 25 million Iraqi's, even if his tour of Iraq had only been 5 days. The American soldiers and their coalition partners have spread freedom to 50 million people in 2 years in 2 separate countries.