Pick on somebody you can beat - like Grenada.
That's not the real issue.
In the first gulf war (desert storm), there were clear goals (push Iraqis out of Kuwait), and they stopped once they had reached those goals.
With the occupation of Afghanistan and Iraq, there were no clear goals and no way of knowing when to stop. That was the big problem.
Of course, there was a reason that there were no clear goals. There was no good reason to invade at all.
Fundamentalism - the anti-American, anti-Christian branch of American Christianity