Flights can be cancelled.
But I think that the Clinton's want Zero to own a massive Goldwater-type of defeat for the Rats. They can ride to rescue in 2016. However won't HRC be too old? Well answering my own question, she will almost be Reaganesque in age by then. So maybe a old socialist has-been running against a youngish (at least young looking!) hopefully successful GOP team. Could be interesting! Watch them find a way to place Chelsea in a congressional seat. (American equivalent of a UK "rotten borough"!)
Interesting irony if that is what they are contemplating.