International conflicts and foreign policy shifts can reshape air travel overnight -- forcing longer routes, driving up costs and causing sudden cancellations or delays.

Cartel violence traps Americans in Mexico after a drug lord's killing. Cruise passengers who have booked voyages with stops in Puerto Vallarta, Mexico, may see their ships diverted this week due to a wave of violence ushered in by the killing of cartel leader Nemesio Oseguera, known as "El Mencho.