What, if any, risks are the politicians (like Susan Collins) running by saying that they cannot support Trump. If he were to win, would Trump try to punish her?

The last couple of days have brought out some Republican politicians who have announced that they could not vote for Trump, no matter what. These include Maine’s senator Susan Collins, as well as several members of the House of Representatives.

And yesterday fifty diplomats and national security types announced that they couldn’t support Trump, because of his recklessness and the damage he has done and could do to foreign relations.

But supposing Trump wins?

Are these politicians and foreign affairs experts putting themselves at risk of retribution? Could / would Trump try and lash out at people who didn’t support him?

What kind of risk are these people taking?