Most travel insurance plans provide coverage for trip cancellation. This benefit provides reimbursement for pre-paid and non-refundable trip cost if the traveler cancels the vacation for a covered reasons. Some plans list terrorism as a covered reason to cancel. Normally, the event must be labeled a terrorist act by the U.S. government. The plan may require that the act be within a set amount of time from the departure date and that it occur in a city listed on the travel itinerary. Always refer to the certificate of insurance for details.