What we did wrong was nation build.
In 2003, that same Dick Cheney was the Vice President of the United States, and he telling people that an invasion of Iraq would not be difficult at all. I believe he used the term "cakewalk" in at least one media interview on the subject.
I guess it's not unusual to see men get dumber with age, but not in that age group. I'm still wondering what facts -- if any -- helped changed Mr. Cheney's mind between 1990 and 2003.
What we did wrong was nation build.
We got into the 2003 because we didn't take out Saddam in 1991. The thinking was we'd get into another war if we didn't take steps to clean things up and put a government in power.