Some of our homegrown firebugs have been known to shoot bottlerockets out car windows while driving and not even needing to stop to start fires.A little tweak with something like paraffin would easily increase the effectiveness.
Travis,I've worried about your theory for years.It's just too easy for anyone to pull off in a number of ways.Think about what could be done with fusees and an airplane,I'm sure the terrorists have.
Pray for rain and lazy unimaginative terrorists.