When I presented a Land Warfare Paper at the 1997 annual meeting of the Association of the United States Army on the Iran-Iraq War I was asked if the invasion that went from an assumed cake walk to an 8-year war of attrition should teach us anything. Wouldn't we just clobber anybody with overwhelming force (like 1991) and wouldn't we just pack up and leave if it got too rough as we did in Vietnam?
I want to quote part of that paper here again:
Not wanting to repeat our experience in Vietnam, many speak of needing an "exit strategy" before committing troops. Such an approach seeks to minimize our losses under the assumption that we will at some point lose, so we had better know when to cut our losses and get out. It also assumes that the situation allows for an exit and that our enemy will allow it. The Iraqis desperately wanted out of the war they initiated in 1980 but were locked in by Iran in a death grip that allowed for no easy exit. While planning for a tough, resilient enemy is prudent, we must never become paralyzed by concentrating on how that enemy can hurt us. We need to keep our focus on achieving victory.
Our enemy in Iraq won't let us just go home to lick our wounds and battle for the White House in peace. That's really the key to shooting down the idea that we must immediately pull out of Iraq and let the Iraqi government fend for itself. Our jihadi enemies who have invaded Iraq to fight us there will fight us wherever we go. Remember that we didn't start this war. And if we go home, with our tails between our legs, our enemies will follow us here--again.
Our enemies will try to hurt us wherever we are. So let's focus on achieving victory, shall we? The way home goes through al Anbar province. And draw some encouragement from the fact that if we stay long enough, we create an ally that will fight our enemies at our side and free us to fight elsewhere on our terms.