Iraq is to part of the war on terror, the mission of the united states from the outset was not only to eliminate al-queda put to eliminate all regimes that were hostile to the united states, iraq is the first country to go down, other countries will be next if they dont cooperate with us.
as for his aproval rating you are correct that his current aproval rating is 52%
but thats not because of the war on iraq, because his aproval rating during the war on iraq jumped from 60% to 71%
source
http://www.foxnews.com/story/0,2933,98928,00.html
but still he has retained the aproval of the majority of americans despite all of the negative press the liberaly biased media has thrown at him, and it infuriates the liberals thats why there so vicious in their attacks because they cant understand why the majority of americans agree with him.