I flew JFK-BEY once and the flight was diverted to AMM because of Israeli military activity in Lebanese airspace. I did not have a Jordanian visa at the time (you had to get the visas in advance back then) and I suspect most of the passengers on the plane did not either. Somehow it was all worked out through the airline and the hotel that the airline put us up in. we were flown to BEY the next day.