The United States used mujahedeen to drive the Soviets out of Afghanistan in the 80s. For a well-written history of how we armed and trained the forces we now fight, read "Ghost Wars" by Steve Coll.
I'm not criticizing the policy decision to give the Soviets their own Vietnam; I'm just responding to your request to enlarge on a previous statement.
Had the Soviets won in Afghanistan and a communist regime taken root there, the Soviet Union may not have fallen apart and it may have taken many more years for OBL to get his act together. But all that would only have delayed the jihadists. They've been on the move for a long time; we just didn't notice until 9/11.
Islam has used "special operations" for 1500 years. They frogmarch a thug or pervert to the border of their lands, and then order him to make war on the infidel, or die.
That is how yassar Arafat got into the terrorist biz: caught flagrente delecto with a muscular young man, in Cairo, where he was born.
There are two Sunni organizations that are the dumping ground for thugs and perverts: Al Queda and Hamas. There is one Shiite organization: Hezbollah.
Al Queda uses Wahabi theology, Hamas is more flexible.