Donald Trump began his presidency in a troubling crisis of legitimacy, given charges that Russia meddled in the election to help him defeat Hillary Clinton, and that Clinton won the popular vote nonetheless. This crisis is now devouring him.

From the moment he and his staff began haranguing the media for accurately reporting the size of his inaugural turnout, compared with Obama’s much larger crowds, we have been watching Trump spiral into paranoia. With the firing of FBI Director James Comey, we may be witnessing Trump’s presidency unraveling.

Trump’s cover story for Comey’s dismissal—that brand-new deputy attorney general Rod Rosenstein wanted him gone, ironically due to his handling of the investigation into Hillary Clinton’s e-mail practices last year—has completely come undone in 24 hours. On Wednesday, The New York Times reported that Comey told congressional leaders that days before his firing he’d submitted to Rosenstein a request for resources to expand the Russia probe. By Thursday morning, a half-dozen major news outlets produced deeply reported pieces, some based on as many as 30 sources, revealing that Trump has been seething over Comey’s handling of the investigation into alleged collusion between Trump’s campaign and Russian government officials—and that his anger hardened into a plan to fire him last week. The Washington Post reported that Rosenstein threatened to resign, angry at being falsely depicted as the person behind Comey’s firing. (The Justice Department is denying that report.)

It seems that on May 3, Comey committed his unforgivable sin while testifying before the Senate Intelligence Committee. Trump signaled his anxiety with a tweetstorm the day before. “The Russia-Trump collusion story is a total hoax, when will this taxpayer funded charade end?” one tweet read. Comey sealed his fate when he acknowledged his actions might have played a role in Trump’s victory over Hillary Clinton. It made him “mildly nauseous,” he said, to think he tipped the race to the Republican. Comey himself was confirming Trump’s darkest fear, the font of his angsty, crazy late-night and early-morning tweets: that he hadn’t won the presidency legitimately.

Trump’s biggest mistake in this whole fiasco may have been including this farcical claim in his very short letter of dismissal to Comey: “I greatly appreciate you informing me, on three separate occasions, that I am not under investigation.” If the firing had nothing to do with the very real investigation into Trump’s campaign ties with Russian officials, why would Trump mention it? And if it does have something to do with the Russia-Trump investigation—which far from denying, Comey had publicly confirmed—then Trump is obstructing justice.

If there’s any remaining doubt that his personal legitimacy crisis is driving his crazy behavior, Trump is dispelling it by choosing today to sign an executive order establishing a commission to investigate (false) charges of voter fraud, headed by ace voter-suppressor Kris Kobach. Trump seems so comfortable with the rule-breaking and corruption he mastered in the private sector, he doesn’t completely understand that he might want to shield his personal motivations more artfully. He’s claimed Clinton built her popular-vote margin with illegal voters; now that he’s dispatched with Comey, he’ll use Kobach to slay his other legitimacy phantom.

The big issue is what happens now. So far, influential GOP Senate leaders continue to oppose the appointment of a special prosecutor. Senate majority leader Mitch McConnell came out Wednesday morning and humiliated himself spouting Trump talking points, while Intelligence Committee Chair Richard Burr insisted his committee can continue with its bipartisan investigation. Meanwhile, Senate Democrats seem divided on their next moves. Minority leader Chuck Schumer seemed to threaten to stop all Senate work until a special prosecutor was appointed, but his caucus didn’t go along. “There’s a lot of business we’ve got to be doing right now that is unrelated to this, and I don’t think we should have an overall rule about not doing business,” Senator Tim Kaine of Virginia told The Atlantic, adding: “We can chew gum and walk at the same time.”

By the end of Wednesday Schumer seemed to retreat, stating on the Senate floor: “There are many questions to be answered and many actions that should be taken. We will be pursuing several things in the coming days, and we’ll have more to say about those next steps in the days ahead,” he said in remarks delivered on the Senate floor. Right now, it might take more resistance to strengthen Democrats’ spines. Trump has a legitimacy crisis that may be morphing into a constitutional crisis. We need leaders from both parties to confront it squarely.