Look at JetBlue out east. By all accounts they are extremely successful and leading the industry in many ways. And shortly after 9/11 they announced with pathetic timing, that they were going to place a very large order for more Airbus planes.
9/11 also had a hugh impact on Boeing.
JetBlue's decision to go with Airbus is based on the fact that they already use AirBus exclusively, so they only need to support one line of aircraft. They initially purchased Airbus because they are reliable and cheaper. Now they are leading the industry and are profitable.