One last point on history
Even if you never read it.
But because within a few months or years of our departure, there will be a genocide in Iraq resulting in an instability in the region which will at worst spark an all out multi-party regional war, and at best result in a torrent of terrorist volunteers for generations to come.
There was "genocide" and "regional war" in Iraq before 2003, hundreds of thousands of killings and executions, and the unprovoked invasion of two neighboring nations on two separate occasions. The result was the deaths of over ten times the number of Iraqis that have died in the current war to date. Had Saddam and his sons remained in power, it would certainly have happened again.
That's learning from "history."