I have approximately zero respect for the Republican establishment's judgment. After all, they had no objection to Mitt Romney in 2012 or John McCain in 2008, and both candidates were obvious losers.
What we do know about Donald Trump is that many of his positions are far to the left of any other Republican candidate, and that once he turns his attention to an opponent, it is devastating. I have no doubt that he can take politician-wannabe Hillary Clinton apart piecemeal. There is SO much that's wrong with her: Her health... her personality... the FBI investigations and what they might lead to... Clinton scandals galore.
This argument that the Republican establishment is only afraid that he can't beat Hillary is utter nonsense. When it comes to dismantling an opponent, he's the best there is.
Does this mean that I like Trump or his positions? Of course not. But I think that the generational problem that exists in the Republican Party... the fact that it is joined at the hip to the Democratic Party... may end once Donald Trump becomes the President. He owes them nothing. They don't control him. He can oust the rats and fix the Party from the ground up. That's IMPORTANT.