They don't have to hijack any planes. All they have to do is to coordinate a bunch of guy to say the same story and we'll get all paranoid and worried. They have terrorized us and haven't spent a dime or created one single martyr.

When you have binary-thinking idealogues running this country, it's simple to mess with their minds.

But, how would I take over a plane post 9-11? Use more guys than 4-5. First couple do something that causes the air marshalls to reveal themselves. Second group takes out the air marshalls. Bad guys now own the cabin and have enough people and the recently-deceased air marshall's weapons to deal with any passengers or crew. Not sure how I'd get into the cockpit with reinforced doors. Give me a couple of days to figure it out.