The special counsel overseeing the investigation into Russia's role in the 2016 election is interviewing senior intelligence officials to determine whether President Trump attempted to obstruct justice, officials said. (Patrick Martin,McKenna Ewen/The Washington Post)

Last month President Trump apparently told the Russians he fired FBI director James B. Comey to relieve pressure on him. Except, in firing Comey, Trump has upped the pressure cooker he's in by a factor of 10.

“I'm not under investigation,” Trump then told the Russian foreign minister in the Oval Office, according to the New York Times.

Now, it appears he is.

The Washington Post reported Wednesday that special counsel Robert S. Mueller III is investigating Trump for possible obstruction of justice, related to Comey's testimony alleging that Trump tried to interfere in some of the FBI's Russia investigations.

Until recently, the FBI's investigation had focused on Russia meddling in the presidential campaign and whether Trump's campaign helped. We knew the investigation was looking into Trump's adviser and son-in-law Jared Kushner, but we had no idea how much higher it would go. Now, that investigation has branched out into obstruction into its first investigation. And the spotlight on the obstruction case is entirely on the president himself.

This is the great irony for Trump, an irony he doesn't seem to have comprehended: When he feels backed into a corner, he lashes out in politically inadvisable ways that often makes his life much more difficult. But he can't seem to stop doing it.

As a candidate behind in the polls, Trump lurched at Hillary Clinton in a way that gave her supporters leverage to claim Trump wasn't supportive of women. As a president who watched health-care legislation stall in the House of Representatives, he blamed conservatives in a way that fractured his delicate relationship with Congress. When he tweeted about an impending court decision on his travel ban, a federal court used that against him.

Some of that still worked out for him, some of it hasn't.

But when Trump feels encroached by a serious and multipronged legal investigation, lashing out attracts a different set of consequences for the president: Legal ones that directly threaten him.

“He expanded [the pressure he's in] considerably,” said Jeffrey Jacobovitz, a white collar lawyer who represented officials in the Clinton White House and now is with Arnall Golden Gregory LLP. "That, combined with the recent emoluments clause lawsuits, really leads to the perception of a wall around him." (We'll get to the emoluments lawsuits in a minute. )

Jacobovitz doesn't think it's a coincidence that, last week, a friend of the president said Trump was considering firing Mueller. (A consideration the White House didn't deny: They later said Trump has “no intention” of firing Mueller.)

A few days later, sources with knowledge of the closed-door special counsel investigation leaked to The Post that Trump himself is under investigation. That's a shocking development.

But making the scope public is like a buffer for Mueller's job security — and it could act as a buffer to try to save the president from himself.

“Now it's clear that he's being investigated, it makes it even more difficult to fire Mueller,” Jacobovitz said, “because it looks like he's trying to terminate an investigation against himself. ... It would be political suicide.”

If Trump were to follow through on his natural instinct to lash out and fire Mueller, he would have little support. Pretty much everyone who's anyone in Washington has made clear they think it'd be a terrible, terrible idea for Trump to sack Mueller.

“I think the best advice is to let Robert Mueller do his job,” House Speaker Paul D. Ryan (R-Wis.) told reporters on Tuesday.

For how Trump could, feasibly, fire Mueller, here's a flow chart by Washington Post's Philip Bump, who explains the process in detail here:

That doesn't mean Trump will keep his head down. Especially since things could get even worse for him on the legal front.

Attorneys general for Maryland and the District of Columbia have filed a lawsuit against the president, alleging he's violated the emoluments clause of the Constitution by not fully separating himself from his business. (He retains an ownership stake in the business his sons run.) So has a government watchdog advocacy group. And nearly 200 Democratic members of Congress will soon file a similar lawsuit.

If any one of those gets traction in the courts (and Jacobovitz thinks one will), Trump could be investigated for his personal finances as well as his actions as president. Oh, and Mueller's investigation is also reportedly looking into unexplained “broad financial crimes.”

Add it all up and you have a president who could soon be under attack on multiple legal fronts. Trump's go-to move when he feels under attack is to respond in a way that exacerbates the situation. That's why there's an obstruction of justice investigation in the first place.

At this point, the president has boxed himself into a corner where following his instincts could make his life exponentially worse.