For the past six weeks, an overarching concern for the Republican Party has been the impact that Donald Trump might have on the GOP primary election – particularly the damage he could do on the debate stage by turning an already unmanageable 10-candidate forum into a full-on circus.
On Sunday, though, Trump himself gave one of the clearest examples yet of why his candidacy is doomed to fail, and why, if handled properly, the debate stage could be his Waterloo.
Trump called in to CNN's State of the Union on Sunday morning to speak with host Jake Tapper.
Much of the appearance was, in fact, more of a Trumpian soliloquy, which appears to be his favorite form of expression, than an interview. However, when Tapper was eventually able to interrupt him and press for some policy specifics, the cracks in Trump's façade quickly became evident.
Trump has staked much of his campaign on his promise to solve what many of his supporters see as a major immigration crisis. As anyone serious about the issue of illegal immigration recognizes, there are at least 11 million undocumented workers in the U.S. right now, and rounding them up for deportation is not a viable option.
Tapper asked Trump to expand on his policy beyond building a wall on the border. The host may have been hoping for a considered reply revealing Trump's detailed thinking on immigration.
What he got was a sort of immigration-related word salad.
"We're going to get the bad ones out," Trump vowed. "We have some really bad dudes who are here in this country and we're getting them out. We're sending them back where they came from."
Tapper tried again. What about the 11 million already here?
"The bad ones are going to get out. Then from that point on, we're going to look very, very strongly at what we do. And I'm going to formulate a plan that I think people are going to be happy with. But we're going to look very, very strongly at what we do."
No really, what about the 11 million?
"I'm gonna get rid of the bad ones fast, and I'm gonna send them back. We're not going to be putting them in prisons here and pay for them for the next 40 years."
One more try. There will be millions left. What's your plan?
"We're going to see what we're going to see," Trump finally said. "It's a very hard thing from a moral standpoint, from a physical standpoint, you don't get them out. At least 11 million people – I've heard the number's much higher…
"We're going to take the high ground. We're going to do what's right. Some are going to have to go and some – Hey, we're just going to see what happens. It's a very, very big subject and a very complicated subject."
He added, "The wall's going to be built. We're going to have a great border. People can come into the country legally, but not illegally, and the people that come in are going to be good people are going to be great people and I want that. That's very important to me."
Tapper asked Trump for his thoughts on the mass shooting last week in a Louisiana move theater, with a follow up asking him whether he approves of policies that would make it more difficult for the mentally ill to obtain firearms.
After declaring, "These are sick people. These are very, very sick people," Trump told Tapper that the problem wasn't easy access to guns, but the "mentality" of the people wielding them.
"I'm a big second amendment person," Trump said. "I believe in it so strongly."
"You need protection from the bad ones that have the guns. You take the guns away from the good people and the bad ones are going to have target practice."
Pressed by Tapper to take a position on whether the mentally ill should be denied access to firearms, Trump declined to come out in favor of a ban.
"I think that if a person is mentally ill and it's proven and documented you have to be extremely careful not to let them kill people," was as far as he would go.
Referring to the shooter in Louisiana, who had a documented history of mental problems, Trump suggested that the problem was not that he was allowed to buy a gun, but that he hadn't been locked up in the first place.
"He should be in an institution," Trump said. "He was a very sick puppy."
The former reality TV star also jumped on the opportunity to attack Hillary Clinton, the Democratic frontrunner currently being pummeled by the ongoing investigation of her use of a private email server for her correspondence while Secretary of State. On Friday, The New York Times published a story claiming that two federal inspectors general had asked the FBI to open a criminal investigation into her handling of classified information.
The Times was forced to correct the record after the Department of Justice confirmed that while the FBI was asked to investigate whether there had been a security breach, there was no criminal referral.
That fact, however, didn't deter Trump from not only declaring Clinton a criminal, but also positing a Democratic conspiracy within the Justice Department to shield her.
"What she has done is criminal. What she has done is criminal," he repeated. "I don't see how she can run. Because if the prosecutors, who are all Democrats by the way – that's part of the problem with fairness here, they're all Democrats so they're protecting her. But if you had an impartial prosecutor and they were honorable – and maybe they are -- we're gonna find out but what she's done is criminal."
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Asked by Tapper to outline exactly what he thought Clinton had done that was criminal, all Trump could manage was, "The whole email scandal. It's a scandal. And she's been protected."
If any of Trump's potential debate opponents were watching, it should have been a very instructive few minutes. Even on Trump's signature issue, his policy positions are tissue-thin, and don't stand up to the lightest questioning.
Why he begins to be required to answer substantive questions – and to defend his answers – in a forum he doesn't control, The Donald may just end up firing himself.