In similar straits, Richard Nixon was confronted by a Democratic Congress. Trump’s ace in the hole is a Republican Congress — unless it turns on him. Photo: Don Carl Steffen/Gamma-Rapho via Getty Images; Saul Loeb/AFP/Getty Images

The morning after the president’s abrupt firing of FBI director James Comey, an account of what was really going on is beginning to emerge in which the official explanation of steadily mounting, retroactive bipartisan dismay with Comey’s handling of the Clinton email case is but a flimsy pretext. Politico boils down the background story succinctly:

[Trump] had grown enraged by the Russia investigation, two advisers said, frustrated by his inability to control the mushrooming narrative around Russia. He repeatedly asked aides why the Russia investigation wouldn’t disappear and demanded they speak out for him. He would sometimes scream at television clips about the probe, one adviser said.

And so he decided to drop the hammer on Comey at the first convenient opportunity. A screwup in Comey’s description of the emails on Anthony Weiner’s laptop that were the subject of the FBI director’s famous October surprise provided the immediate excuse. It seems clear that Team Trump believed Democrats would be thrown into disarray by the clever use of the Clinton emails as the rationale for a firing that was really about something else.

That calculation was clearly wrong, but the fact remains that if Trump’s move was intended to curb the Russia investigation, his enemies have limited means of stopping him.

Yes, the FBI can and probably will formally continue the investigation, but the odds are pretty good that whoever Trump chooses as Comey’s immediate successor will treat it as a very low priority.

The Justice Department can — and given the recusal of the attorney general, Jeff Sessions, on matters related to the Russia-Trump connection, almost certainly should — appoint a special counsel to take over the investigation and clear the air. But why would a White House determined to shut it all down accept that course of action? It’s implausible unless the administration winds up with no other good options.

Congress could create a special committee, or even a congressionally constituted commission, to delve into the various issues involving the Russians. The latter course is what conservative House gadfly Justin Amash talked about doing in the immediate wake of the Comey firing.

But a lot of Republicans would have to go along with that approach, and most significantly in the wall of noise that rose across Washington after the firing was announced, the chairmen of the House and Senate Judiciary Committees — Representative Bob Goodlatte and Senator Chuck Grassley — seemed to be buying the White House/DOJ explanation of the matter. If their posture is that Comey had to go for cumulative sins in the Clinton email case, why would they want to waste taxpayer money on some special investigation of that Russian thingy Democrats insist on talking about? You could see any drive for a congressionally authorized investigation running into some real obstacles. For his part, Senate Majority Leader Mitch McConnell is arguing against any new investigation of Trump and Russia at all, suggesting the Senate Intelligence Committee’s inquiries are sufficient.

Once upon a time, there might have been a wellspring of support for the appointment of an independent prosecutor that would not report to Congress or to the administration. But the law authorizing that institution was allowed quietly to expire in 1999 after its generally conceded abuse in seven separate investigations of the Clinton administration.

As veteran journalist Jeff Greenfield points out, the disarray of Congress is the single most important problem with treating this situation as analogous to Richard Nixon’s “Saturday Night Massacre,” despite the obvious parallels of an angry president trying to dispose of an underling who might be getting too close to securing dangerous information. Nixon was dealing with a Democratic Congress and a much smaller and more uniformly hostile news media; he was quickly forced to replace the fired special counsel Archibald Cox instead of shutting down the Watergate investigation altogether. The 37th president was also laboring under the ultimately fatal existence of massive evidence of wrongdoing documented by his own White House recording system; Cox was fired for trying to secure some of the relevant tapes. If the Trump White House is harboring a “smoking gun” in the Russia case, we don’t know of it at present.

The bottom line is that Trump has a much better chance of getting through this “crisis” than Nixon did when he “massacred” a special counsel and the Justice Department officials defending him. The key thing to watch is whether congressional Republicans decide in large numbers that Trump’s stonewalling over Russia and his generally imperious habits are endangering their grip on the Legislative branch in 2018. If and when that wall breaks, and the GOP no longer feels a need for solidarity with its president, then depending on what is underneath all the furor, Trump and his associates could be in real trouble.