2 More Flights Are Called Off After Warnings. (cover story)

Reports that British and Mexican airlines canceled two flights to the U.S., after U.S. and British authorities warned of possible terrorist threats. Concerns of U.S. officials about two other flights; The government's increasingly aggressive efforts to police American airspace in the face of renewed terrorist threats; Fears of the President George W. Bush administration that terrorists may hijack an international flight; Security efforts, including putting armed marshals on some flights; Details of the cancellations; Implications for air travelers.