Don’t do it, Don’t do it, OK do it

When a whole political party is told not to do it, what should they do?
The London Labour Party was told by Tony Blair not to choose Ken Livingston as Mayoral candidate, then everyone said not to elect Jeremy Corbyn as Labour leader.
Now the bigwigs in the American Republican party are saying not to choose Donald Trump as their candidate for President.
Members of the Republican party are idiots for choosing Trump. But the bigwigs are bigger idiots for thinking that people should do what they are told.