Fact: he was sponsored by Saudi Arabia and Kuwait and the Gulf states
Fact: he had no real ambitions against the West prior to 1991
Fact: the Iranis bled a lot in the Iran-Iraq war, losing thousands of fanatics
Fact: the Saudis sponsor terrorism through their Wahabbi madrassas across the world
Fact: AlQaeda hated Saddam, Assad, Ghaddaffi, Mubarak as examples of secular dictators standing in the way of the Caliphate
That's the key point right there. Now add to that list the Shah of Iran. The US has been very efficient when it comes to removing the local opponents of radical islam. The best you can say is that we been useful idiots.