Retired Gen. Stanley McChrystal said in a rare interview Sunday that he considers President Donald Trump “immoral” and wouldn’t take a job in the administration.

McChrystal, a retired four star general and former top commander of U.S. and international forces in Afghanistan, spoke to ABC News anchor Martha Raddatz about the resignation of Defense Secretary James Mattis and the administration’s Middle East policy.

“If you were asked to join the Trump administration, what would you say?” Raddatz asked.

“I’d say no,” McChrystal said.

“Do you think he’s a liar?” Raddatz followed up.

“I don’t think he tells the truth,” McChrystal said.

“Is Trump immoral in your view?” the ABC anchor asked.

McChrystal: “I think he is.”

When asked what he would say to Trump supporters, McChrystal said he would not tell them “they are wrong.”

“What I would ask every American to do is stand in front of that mirror and say, ‘What are we about? Am I really willing to throw away or ignore some of the things that people do that are — are pretty unacceptable normally just because they accomplish certain other things that we might like?’

He continued: “If we want to be governed by someone we wouldn’t do a business deal with because their — their background is so shady, if we’re willing to do that, then that’s in conflict with who I think we are. And so I think it’s necessary at those times to take a stand.”

McChrystal argued Mattis’ resignation letter was “much broader than the Syria issue — it was about America’s role in the world.” He added he hoped it would cause Americans to “take pause” about someone like Mattis jumping ship from the administration.

“I think maybe it causes the American people to take pause and say, wait a minute, if we have someone who is as selfless and as committed as Jim Mattis resign his position, walking away from all the responsibility he feels for every service member in our forces and he does so in a public way like that, we ought to stop and say, ‘OK, why did he do it?,'” McChrystal said.

Watch above, via ABC News.

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