The AA flight was from Paris. When it was diverted to Hartford, which is supposed to be an international airport but where Customs/Immigration officials are not really required very often, it was held awaiting Customs inspection. The inspectors likely had to come from JFK and were stuck in the snow like everyone else.

All that AA might have done is send the plane someplace else, like Chicago, if they had enough fuel. But once you hear about a 'diversion' - all bets are off. They were totally taken by surprise.

I don't know anything about the Jet Blue flights.

P.S. BDL is not really that small!