Another concern of mine is that there were incidents in the 90s where Cuba interfered with the NYC air traffic control system, and Cuba's very recent cozying up to Iran, where Castro spoke before their politicians about bringing the US to its knees, together with Iran.
Something bigger than just al-Qeada has been going on.
I seem to recall a biography on McVeigh where after the Gulf War he had started expressing sympathy towards the Iraqis. I wonder if this led him to Islamic groups within the US? Just a thought.