(CNN) It's still a mystery what exactly occurred and who exactly was involved, but a new report suggests a US intelligence official filed a whistleblower complaint against the US President for, as the Washington Post reported , making a "promise" of some kind to a world leader.

That an intelligence official was so distressed as to move against President Donald Trump in such a formal way is a remarkable development at a time when Trump's actions might have had you thinking it was not possible to be shocked any more.

Trump says there's nothing to see here.

"Virtually anytime I speak on the phone to a foreign leader, I understand that there may be many people listening from various U.S. agencies, not to mention those from the other country itself. No problem!" he said on Twitter after the report was published by the Washington Post. "Knowing all of this, is anybody dumb enough to believe that I would say something inappropriate with a foreign leader while on such a potentially "heavily populated" call. I would only do what is right anyway, and only do good for the USA!"

But his talks with world leaders, in public, on the phone and in private, have frequently dropped jaws to the ground either for their unprecedented nature, their awkward details or their instant reversal of US policy.

He gave classified information to the Russian ambassador and foreign minister

The day after he fired James Comey as FBI director , in part for not quashing the Russia investigation, Trump revealed classified information to the Russian foreign minister and then-ambassador during a meeting with the two in the Oval Office. The Russians later posted pictures of the meeting on social media.

Trump in the oval office with then-Russian Amb. to the US Sergey Kislyak.

He might not tell us about his interactions, but the Russians will

Sometimes we find out about such interactions from the foreign country, such as when the Russian government posted about a call Trump had made to Putin and the White House waited hours to confirm it occurred. According to the White House, the call was about wildfires in Siberia and trade. According to the Russians, the call included a promise of help from the US in dealing with the fires.

"The President of Russia regards the US President's offer as a sign that it is possible that full-scale bilateral relations will be restored in the future," they posted on Facebook July 31. They also said the two had committed to routine phone calls in the future.

He gives the impression he's agreeing with Putin

Trump's meetings with Putin are routinely cause for concern and there have often been different interpretations about what happened in the meetings, such as when the Russians said after a two-hour meeting in July of 2017 that Trump accepted Putin's assurances that Russia had not interfered in the US election.

Then-Secretary of State Rex Tillerson said Trump had raised the issue and the two had a robust conversation.

He met alone with Putin and there are no detailed notes of what transpired

Trump has met alone with Putin on the sidelines of large gatherings of world leaders. In January, there were reports that Trump, perhaps fearing leaks, has gone to great lengths to keep details of what was discussed during his private talks with Putin even from his top aides. There are no detailed records of many of his talks with Putin.

"You sit with the president of various countries," Trump said on Fox News in January after the report in the Washington Post . "I do it with all countries. We had a great conversation, we were talking about Israel and securing Israel and lots of other things and it was a great conversation. I'm not keeping anything under wraps. I couldn't care less."

He changes US policy on a whim

Trump gave many concessions to North Korea's leader Kim Jong Un as he sought an historic nuclear agreement, first in Singapore in 2018 and then at a second summit in Vietnam in 2019. Notably, he promised to drastically curb US military exercises with South Korea, which Trump, speaking up for North Korea, described as "provocative." It was a move that took the US military by surprise

He admits things to world leaders he won't admit to American citizens

Shortly after taking office, leaked written transcripts of calls between Trump and then-President of Mexico Enrique Peña Nieto, he asked repeatedly for the Mexican President to stop saying Mexico would not pay for the border wall. Trump said he'd been telling his supporters for years that they would. And he knowingly suggested it would "come out in the wash." But he needed a commitment that they wouldn't publicly make an issue of it any more.

He also sought to allay the Mexican leader by saying the wall was the least important thing they were talking about even though the wall was the centerpiece of his presidential campaign and is the policy goal that has defined his presidency.

He can become frustrated

While deferential to leader like Putin and North Korea's Kim, Trump can become frustrated with other world leaders, as he did with then Australian Prime Minister Malcolm Turnbull. Trump didn't want to honor an agreement between Turnbull and President Barack Obama regarding refugees. After a long and contentious back-and-forth, Trump told Turnbull, "I have had it. I have been making these calls all day and this is the most unpleasant call all day. Putin was a pleasant call. This is ridiculous."

He can berate US allies in their own country

Trump criticized then-UK Prime Minister Theresa May during an interview with a British tabloid while he was in England in July of 2018.

"I told her how to do it," he said of May's approach on Brexit at the time, according to audio posted by the Sun . "That will be up to her to say. But I told her how to do it. She wanted to go a different route."

He also seemed to endorse current Prime Minister Boris Johnson in the same interview.

He can't take criticism

His bromance with French President Emmanuel Macron may have already been on the rocks, but a phone call between the two on trade and migration went "horribly" after Macron criticized Trump's policies, sources told CNN's Michelle Kosinski and Maegan Vazquez. Trump had recently announced new steel tariffs and he had a similarly tense call with May.

He also had a tense call with Canadian Prime Minister Justin Trudeau about tariffs in June of 2017. The White House described that call as "amicable." The Canadian version of the readout suggested Trudeau disputed "baseless" claims by the US Department of Commerce about Canadian lumber and described him as promising to "vigorously" defend Canada.

He makes things up

But it's another meeting with Trudeau that is more telling . Trump told supporters at a fundraiser in Missouri in 2018 that he insisted during one meeting with Trudeau that the US has a trade deficit with Canada -- that it buys more from Canada than it sells to the country. Trudeau was right that the US has a trade surplus with Canada.

"I said, 'Wrong, Justin, you do.' I didn't even know. ... I had no idea. I just said, 'You're wrong,'" Trump recalled. "You know why? Because we're so stupid. ... And I thought they were smart. I said, 'You're wrong, Justin.' He said, 'Nope, we have no trade deficit.' I said, 'Well, in that case, I feel differently,' I said, 'but I don't believe it.'"

Trump later argued on Twitter, despite the facts published by his commerce department, that there is a deficit.

He can come away with weird ideas about something serious like the climate crisis

JUST WATCHED Trump says US should rake like Finland to avoid fires Replay More Videos ... MUST WATCH Trump says US should rake like Finland to avoid fires 02:34

After a meeting with Finnish President Sauli Niinistö, Trump suggested during a tour of California wildfires that authorities there might consider raking more in American forests.

"I was with the President of Finland and he said we have -- much different -- we are a forest nation. He called it a forest nation," Trump said. "And they spend a lot of time on raking and cleaning and doing things, and they don't have any problem. And when it is, it's a very small problem. So I know everybody's looking at that to that end."