I'm no fan of Saudi Arabia, but their government is a target of Al Qaida cells, whereas Iraq's government was an ally of Al Qaida. Heck, there have been (and most likely are) Al Qaida in America but we won't be invading ourselves anytime soon.
Here is my honest sentiment on the Iraq War: I like seeing al qaida get killed and lining up to get killed; however, I do not like to think of the USA as the “hired hessians” for the House of Saud and the other Arab weak sisters. They need to tow the line and pay in blood, not just oil, for their safety. Saddam was their problem, and Israel’s, but not the UN’s or the USA’s.
Al qaida is a sunni group; Iran is shia. These are our two top “muslim facist” foes (though I wonder what Iran has done that can’t be traced back to decades of US gaming them both internally and against Iraq). Why not step aside and let them wreak their violence upon each other until they see the light (if ever)? I am afraid the answer is because we need oil and its free flow through the straits.
I know these ideas will chap some folks’ hides, but this is the way I currently see it. I am open to counterargument.