(CNN) The official spin around the news - - confirmed by President Donald Trump -- that White House counsel Don McGahn will be leaving his post this fall goes something like this: We always expected Don to serve through the first two years of the administration. This is a very stressful job, and Don always said he wouldn't and couldn't stay in the role for the entire first term.

Which is, in part, true. Being the lead attorney in any White House is stressful. Being the lead attorney in the Trump White House is roughly equivalent to my stress level when one of my kids is the first performer at a piano recital.

But, but, but. Context matters -- HUGELY -- here.

And the context is this: We learned 11 days ago that McGahn had sat for interviews with special counsel Robert Mueller's team for more than 30 hours in the course of the investigation into Russia interference in the 2016 election. We also learned that Trump himself was unaware that McGahn had spent so much time with Mueller's team, and that the White House more broadly was unaware of what exactly McGahn had told Mueller.

That news "unnerved" Trump, according to CNN reporting . This paragraph, from CNN's report on Trump's reaction to the McGahn news, is prescient and telling:

"The meetings only add complications to the already-fraught relationship between the President and the White House's top lawyer. And as nervous aides await a verdict in former Trump campaign chairman Paul Manafort's trial and watch with trepidation the inauspicious public relations blitz carried by lead attorney Rudy Giuliani, uncertainty surrounding the President's handling of the Russia investigation abounds."

While trying to downplay the news, Trump made clear that it irked him. "The failing @nytimes wrote a Fake piece today implying that because White House Councel Don McGahn was giving hours of testimony to the Special Councel, he must be a John Dean type 'RAT,'" Trump tweeted . "But I allowed him and all others to testify - I didn't have to. I have nothing to hide."

When asked Wednesday whether he was worried about what McGahn told the special counsel, Trump said, "No."

"We do everything straight, we do everything by the book, and Don is an excellent guy," the President said.

Step back even beyond this month -- and think about the role McGahn has played in this White House. According to The New York Times, Trump tried to force McGahn to fire Mueller as special counsel last summer but ultimately backed down when McGahn refused to carry out the order. Trump also ordered McGahn to tell Attorney General Jeff Sessions not to recuse himself in the Russia investigation, according to the Times. (Sessions recused himself anyway.) And McGahn was the person that then-Acting Attorney General Sally Yates sought out to inform him that Trump national security adviser Michael Flynn was lying about the nature of his contact with Russian officials -- and likely misled Vice President Mike Pence on that matter. (Trump fired Flynn for lying to Pence.)

So. What we know is that a man intimately involved in several of the most high-profile moments in the first 18 months of the Trump White House (and who was a legal adviser to Trump's campaign) is now leaving -- news that broke less than two weeks after the President was caught by surprise by McGahn's level of cooperation with the special counsel.

Or, let's make it even simpler: The man who single-handedly kept Donald Trump from firing Mueller is now leaving the White House, 11 days after the extent of his cooperation with that same special counsel was made public.

There is no such thing as coincidences that big in American politics. Just doesn't happen. McGahn -- and Trump -- knew exactly the sort of signal the announcement that McGahn was leaving would create. The reaction of Judiciary Committee Chairman Chuck Grassley to the news sums up that sentiment nicely: "I hope it's not true McGahn is leaving White House Counsel," Grassley tweeted at Trump . "U can't let that happen."

(It's worth noting that Trump didn't announce the news on Twitter because he wanted to. He did so because Axios reported the news of McGahn's imminent departure early Wednesday morning.)

If McGahn's departure had nothing to do with the ongoing legal and political swirl created by the Mueller probe, he could have easily delayed his departure into the private sector for a few more months -- maybe lasting until after the Mueller report was released. He isn't. That's telling.

Make no mistake: None of this is "going according to plan" for the Trump administration. McGahn's departure takes an already difficult situation for this White House and this President and makes it that much tougher. No spin can change that basic fact.