There was an actual lengthy, substantive discussion on Morning Joe this morning with Tim Snyder, a history professor and the author of the best-seller "On Tyranny: Twenty Lessons from the Twentieth Century," Willie Geist, and Joe Scarborough.

Snyder reminded them that "most republics and most democracies fail," and that history provides tools to help. "Because a lot of the things that are happening to us are just the early stages of processes that happened elsewhere."

Geist asked what parallels he saw with current events.

Snyder noted the recent "loyalty" conflict with Trump and Comey.

"First of all, the idea of loyalty. Loyalty is a way you take a rule-of-law state like ours off the rails and transform it into something else," he said.

"When the president asked the FBI director for loyalty, he's actually trying to change the character of the American government. Hitler in 1934 began to demand precisely loyalty, and it was from that moment forward that he was the leader and no longer just the chancellor of Germany," he said.

"Or, for example, firing Mr. Comey by sending over a head of a private security detail. That's what happens in Germany as well. The private security detail eventually becomes the SS and they become more important than the police. It's a baby step forward to use the head of your private bodyguard to fire the FBI director, but it's a troubling indication of the way this man's mind works."

Scarborough asked him to clarify. "When you use the term Nazis, all kind of alarm bells obviously go off. You're not comparing right now what you see in Donald Trump to Adolf Hitler or the Nazis."

Snyder wasn't reassuring.

"It's important history gives us a sense of possibility," he cautioned. "As you said earlier, Americans tend to be trapped in our own history and we forget it very quickly. We're overwhelmed by daily events.

"What we need to remember is that we're not so much wiser and more capable than Germans in the 1930s. Things that happened to other people can also happen to us.

"The point is that not we're exactly the same -- the point is we should be modest, we should be open to the possibility that things can go very wrong and we should try to learn. If we see a warning sign like loyalty or like a bodyguard taking over functions of the state, we should learn from that rather than saying it can't happen here.

"When you say it can't happen here, you're making it happen here."

Scarborough said he thought our institutions responded properly, especially the courts.

"I had a very conservative judge tell me 'We are all shoulder-to-shoulder against this president overstepping.' Congress actually pushed back on the president's own health care plan, eventually passing something, but he seems to be tied up there as well," the host said.

"While we need to remain vigilant, and i agree with you we must remain humble about the possibility of it not ever being able to happen here, that we're somehow beyond all of this, can't you look back at the last 120 days and say there are several parts of our system that have actually checked out quite well?"

Snyder said he agreed, but with a very important proviso.

"The system doesn't work like a machine -- the system is us. So when Americans say the institutions are going to protect us, my response is ask not what the institutions are going to do for you, ask what you can do for the institutions," he said.

"So insofar as coverage, the press has helped, it's because people in these institutions have been aware of the lessons of the past and have tried to get out front. when people went to protest the muslim bans at the airports, it was because they understood the logic of politics like that and got out front. history is a way for us --"

Scarborough asked Snyder if he agreed that it's "chilling" is that so much of our constitutional republic depends on having a chief executive who operates in good faith. "That perhaps it is too dependent on that fact when you have a president that can appoint an attorney general, can hire and fire an FBI director with absolutely no oversight?"

"The main lesson that we have from 20th century history and the collapse of democracy in the overreach of executives is that it's important not to see moments like this as normal," Snyder stressed.

"And as you say, it's important not to imagine that executives will always behave normally. the chief lesson is you have to recognize moments when the actions of citizens matter more than other moments and that you only have a few months or a year at the beginning to react fast. as you say, some of us have done that.

"You can't count on checks and balances to work on their own. They have to be pushed and nudged along."

Amen.