Was it a mistake for Donald Trump’s opponents in the Republican primary not to have done oppo research on Trump and uncovered the stories about his personal behavior that have recently emerged?

On today’s With All Due Respect, Mark Halperin posed the question to GOP consultant Susan Del Percio [who had earlier indicated she wasn’t voting for Trump or Hillary]. Del Percio said that, indeed, it was “political malpractice” for Trump’s primary opponents not to have done such digging on him. She surmised that the candidates didn’t want to spend the money, and were worried that in retaliation Trump would have “chop[ped] them off at the knees.” Del Percio suggested that the smarter way to go would have been for an anti-Trump super PAC to have done the research.

Questions for LI readers: if these sort of stories had emerged during the primaries, would they have deprived Trump of the nomination? And if one of the other primary candidates had won the nomination instead of Trump, where would the race be today?

MARK HALPERIN: Susan, I’m fascinated by this question for history: is it possible that all of the 15 other Republicans who ran for president committed malpractice by not ferreting this stuff out, and if they had, would it have stopped Donald Trump from being the nominee?

SUSAN DEL PERCIO: I think at the end of the day, some of them just did not want to spend the money on the opposition research that you needed to do. And it was political malpractice not going after him, looking at it today. Because at the time, none of the Republicans wanted to go after Trump directly because they knew he would just take them down and chop them off at the knees. That being said, there certainly are a lot of donors who played it wrong, saying, well, Donald Trump’s going to back out. They could have gotten together and done a super PAC just to take him down, which would have been historically I think the right way to go.