A question about Sen. John McCain sets off President Donald Trump

President Donald Trump is still clearly irritated that his on-again, off-again foil Sen. John McCain derailed the GOP health-care bill that Trump backed.

At a Tuesday news conference, Trump was asked about McCain's defense of H.R. McMaster, Trump's national-security adviser, from attacks from alt-right critics.

McCain, R-Ariz., is the chairman of the Senate Armed Services Committee and a McMaster fan.

Trump responded with a non-sequitur.

"Senator McCain? You mean the one who voted against 'Obamacare'?” Trump shot back. "You mean Senator McCain who voted against us getting good health care?"

McCain did vote against the Affordable Care Act, which Trump and others call "Obamacare," seven years ago. But Trump clearly was referring to McCain's July 28 deciding vote against the Senate Republicans' "skinny repeal" legislation, which effectively killed the current GOP push to undo the Affordable Care Act, a signature achievement of former President Barack Obama.

Later, Trump mentioned McCain again when he was asked about another legislative priority of his, infrastructure.

"We came very close with health care. Unfortunately, John McCain decided to vote against it at the last minute," Trump said. "You'll have to ask John McCain why he did that. But we came very close to health care. We will end up getting health care, but we'll get the infrastructure. And actually, infrastructure is something that I think we'll have bipartisan support on. I actually think Democrats will go along with the infrastructure."

'Disgraceful' attacks

In a statement released Monday, two days after a white-supremacist rally in Charlottesville, Virginia, erupted in deadly violence, McCain, who is undergoing treatment for brain cancer, urged Trump to defend McMaster from "disgraceful" attacks from the alt-right.

"Since this fringe movement cannot attract the support of decent Americans, it resorts to impugning the character of a good man and outstanding soldier who has served honorably in uniform and sacrificed more for our country than any of his detractors ever have," McCain said in his written statement. "Such smear tactics should not be tolerated and deserve an emphatic response. I hope the President will once again stand up for his national security adviser and denounce these repugnant attacks, which arise from the same purveyors of hatred and ignorance who precipitated the recent violence in Charlottesville.”

To McCain's actual point, Trump said to the reporter: "Well, I don't know. I can't tell you. I'm sure Senator McCain must know what he's talking about. But when you say the alt-right, define alt-right to me. You define it. Go ahead. No, define it for me. Come on. Let's go."

Trump then asked, "What about the alt-left?"

"Excuse me, what about the alt-left that came charging at the, as you say, the alt-right. Do they have any semblance of guilt?" Trump asked.

Trump and McCain, who was the 2008 Republican presidential nominee, have been publicly feuding on and off for the past two years. Trump's latest volley was mild compared with some of his past shots at McCain.

McCain's office declined Tuesday to respond to Trump's latest shot. But since McCain's vote against the GOP health-care plan, two national polls have shown his popularity among Democrats soaring.

Dan Nowicki is The Arizona Republic's national political reporter. Follow him on Twitter @dannowicki.

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