Busses and trains aren’t good targets for terrorism. You blow up a bus, maybe no one really cares except the locals to the area where the bus blew up. A plane

Busses and trains aren’t good targets for terrorism. You blow up a bus, maybe no one really cares except the locals to the area where the bus blew up. A plane cuts through many different social classes and nationalities, putting them all in one place and making a large amount of people imagine themselves as the potential victim.