jero- there are protected strikes and unprotected strikes. protected strikes your employer can't take any action agaisnt you, however an unprotected strike and they can kick you out the door with no notice needed, and if it is found that your union condoned your actions they can be liable for any losses the company suffers.
in the uk supportive strike action is illegal!
you can only have a protected strike action for lawful reasons, so striking because someone was fired because they didn't want to fly the affected routes would be illegal, hence unprotected.