"Pyrrhic victories, strictly defined, refer to military victories won at great military cost. There are other types of Pyrrhic victories. To trade our republic for empire, because we walk in unwary of the cost of conquest, occupation and control, is one of these. It's happened before, to the last great republic."

But show where it's happenned in this great republic? There have been no shortage of opportunty for the USA to this, yet we have been very disinclined to take this path. For instance, even our wealthy northern friend Canada, wouldn't have an easy path if they chose to become part of the US. And Mexico wouldn't have a chance in hell. Mexico is in comparison to Iraq, would be much more attractive.
The simply fact is it will cost us money to overthrow Iraq, it will continue to cost us money to occupy Iraq. We rather not do it, but are forced to the task by the threat of the consequences of not doing something which would resolve "this issue".
We would like to stop paying money to Israel. You "could" say that we are continuing to pay money to Israel, partially because we didn't do enough to prevent the Jews from being slaughtered by another madman, and the general prejudice that western civilization has had in regard to Jews. There are of course practical security reasons for our continued support of Israel (which are less significant after the Cold War, but in other ways still as important). Now, this *obligation* is "messy & not straight forward", but I bring it up because we could find in the future that we have a certain type of "debt" because we failed to do the right thing in regards to say the Kurds or people of Iraq in general. Afterall, we even helped this madman, we have the means of getting rid of this disease- inaction is not a guiltless postion. It's an easier postion, a very common human "choice", and throughout history has been proven to have very bad consequences.
I'll close with an explosive statement: The Iraq people are in similar position of Black Americans were prior to the civil war. That might cause some outrage- but it's true. This is about freedom. Freedom for us, and freedom for others. Freedom ain't easy & cheap.