Why is America fighting an Endless War in Iraq?

Interesting question. My guess is the ability of the huge Military-Industrial complex to make or break a Congressmen/women's ability to get elected and stay in office for 20 or so years. Most likely the reason, real reason for going to war in Iraq was Big Petroleum wanted the oil fields of Iraq. What better way to gain control of them than to have the US Military take control of the Country. Right?