Iraq War vs Mexican War

Iraq, in general, has fallen by the wayside in many of our minds. We think of it as a failed war, a drain of the economy, etc. However, the news article "A New Chapter in Iraq" found at www.politico.com by Thomas R. Nides elaborates on the successes of the Iraqi people, despite their close call with a civil war. In my opinion, the similarities between the Mexican-American War and the Iraq War are few, while the differences are many. I can only think of two differences: both were fought in relative deserts, and both were by no means popularly supported. The differences are much more numerous. In Mexico, we were fighting a neighbor. Iraq is halfway around the world, though the term "neighbor" can be used rather loosely in today's internationally connected world. Also, in Mexico, we had declared war against a country, with formal military and generals. In Iraq, at least after ousting Saddam Hussein, we worked more to stabilize the country, while rooting out insurgents that could easily blend in with the innocent. This brings me to another similarity I hadn't previously thought of. Our reasoning for going into Iraq was because of the military rule of Saddam Hussein. However, could it have also been for oil, or influence in the Middle East? Did we not fight for similar reasons in Mexico?