McClatchy reported on Friday evening that special counsel Robert S. Mueller III’s team has evidence of a trip by President Trump’s personal lawyer to Prague in the late summer of 2016. Overseas travel to non-Russian countries might strike some observers as an incremental — if not unimportant — development in Mueller’s probe. That is not the case. Confirmation that Cohen visited Prague could be quite significant.

A trip to Prague by Cohen was included in the dossier of reports written by former British intelligence official Christopher Steele. Those reports, paid for by an attorney working for Hillary Clinton’s campaign and the Democratic National Committee, included a broad array of raw intelligence, much of which has not been corroborated and much of which would probably defy easy corroboration, focusing on internal political discussions in the Kremlin.

Cohen’s visiting Prague, though, is concrete. Over the course of three of the dossier’s 17 reports, the claim is outlined — but we hasten to note that these allegations have not been confirmed by The Washington Post.

It suggests that Cohen took over management of the relationship with Russia after campaign chairman Paul Manafort was fired from the campaign in August (because of questions about his relationship with a political party in Ukraine). Cohen is said to have met secretly with people in Prague — possibly at the Russian Center for Science and Culture — in the last week of August or the first of September. He allegedly met with representatives of the Russian government, possibly including officials of the Presidential Administration Legal Department; Oleg Solodukhin (who works with the Russian Center for Science and Culture); or Konstantin Kosachev, head of the foreign relations committee in the upper house of parliament. A planned meeting in Moscow, the dossier alleges, was considered too risky, given that a topic of conversation was how to divert attention from Manafort’s links to Russia and a trip to Moscow by Carter Page in July. Another topic of conversation, according to the dossier: allegedly paying off “Romanian hackers” who had been targeting the Clinton campaign.

There is a lot there — but it hinged on Cohen’s having traveled to Prague. If he was not in Prague, none of this happened. If he visited Prague? Well, then we go a level deeper.

McClatchy notes that there is no evidence of who, if anyone, Cohen met with, but that the time frame was in late August or early September, as the dossier suggests.

Which brings us to the other reason this development could be significant.

Cohen, for months, has consistently argued that he never made any such trip.

When the dossier was first published by BuzzFeed, Cohen replied to this allegation specifically in a somewhat odd tweet.

Since countries don’t stamp the front of your passport when you visit, it is not clear what this was meant to show. Nor would showing his passport have been exculpatory if he’d shown, say, a stamp from having entered France or Spain, since travel within most of the European Union doesn’t require additional checks at individual borders.

That, in fact, is what McClatchy alleges: That its sources say Cohen entered the Czech Republic through Germany. A Czech publication reported shortly after the allegation was made that government intelligence officials in that country had no record of Cohen’s visiting. One source said that “if there was such a meeting, he didn’t arrive in the Czech Republic by plane.” McClatchy’s report doesn’t contradict that.

The day after Cohen’s tweet, Trump held a news conference.

“He brings his passport to my office,” the then president-elect said in response to a question. “I say, ‘Hey, wait a minute.’ He didn’t leave the country. He wasn’t out of the country. They had Michael Cohen of the Trump Organization was in Prague. It turned out to be a different Michael Cohen. It’s a disgrace what took place. It’s a disgrace and I think they ought to apologize to start with Michael Cohen.”

That part about the “different Michael Cohen” doesn’t seem to be true. Nor does the part about Cohen not having left the country.

Cohen showed his passport to BuzzFeed. The only travel into the proper area indicated by passport stamps was a trip to and from Italy from July 9 to 17. But note that this is too early for Steele’s time frame — and for the assertion that it was a response to the firing of Manafort. How Cohen would have gotten to Prague is still unclear.

But this contradiction between a clear allegation from the Steele dossier and the assertion that it wasn’t true by Cohen and Trump helped drive the idea that the dossier was broadly discredited shortly after its release. Pick out the Prague trip and nothing that follows could have happened. Put the Prague trip back into the mix? A lot of the other parts of that allegation now become possible.* What’s more, it undermines the credibility of those who insisted that the claim was completely without merit.

Look at it another way: If the central conceit of the Steele’s claim were accurate — that Cohen was working with agents of the Russian government directly to aid Trump’s candidacy — it would be very hard to argue that no collusion took place. That likely requires Cohen’s having been in Prague.

This is our first significant indication that he might have been.

* It’s easy to cherry-pick some aspects which ring true. For example: A source of leaked information from the Democratic National Committee who claimed to be Romanian was actually a Russian intelligence official. Carter Page denied having met with Russian officials during his trip in July, until the House Intelligence Committee got him to admit that he had, however briefly. But much more of the dossier’s allegations lacks any resemblance to what is known.