In the event of a war or a heightened terror alert, airlines may decrease the frequency of flights on some routes or cut out routes entirely.

If your airline cancels a flight: If a flight is canceled because of decreased demand, the airline will generally try to get you on a flight with another carrier flying the same route. For flights canceled due to acts of God, international hostilities, or war, most major airlines' contracts of passenger carriage provide for a full refund. Airlines can change their carriage policies at any time, so inquire about them when you book your tickets. An airline's current contract of carriage can usually be found on its website, too.

If you decide not to fly: Most major airlines have adopted more lenient ticketing policies to address travelers' fears about flying during times of conflict. Policy details vary by airline. Make sure to check the ticketing policy when you make your reservation, and again if you have second thoughts about traveling as your departure date approaches.