Vice-president Mike Pence is starting to cast a very long shadow indeed in Washington. Events are brewing that, just possibly, might make him the most consequential second fiddle, though perhaps not for long, in recent American history.
Either the noose is really beginning to tighten around the Donald Trump administration regarding connections between his campaign and Russian intelligence, or one of the most ridiculous comedies of error in American memory has been playing out in recent weeks.
While it might all be a massive farce rather than a tragedy, it’s not too early to speculate about what, if things start to completely unravel for Mr Trump, the endgame might look like.
His first national security adviser, Michael Flynn, was fired after he lied to Mr Pence and the FBI about phone calls with the Russian ambassador to the United States, Sergey Kislyak, in which they discussed sanctions imposed by the outgoing Obama administration.
Now, attorney general Jeff Sessions has been caught in an equally blatant lie about contacts with this same senior Russian diplomat and, almost certainly, key intelligence official.
Mr Sessions told the Senate, verbally and in writing, that he had had no contact whatsoever with Russian officials during the campaign. But, in fact, he met the ambassador twice. He is now thoroughly tainted and has recused himself from the Russia investigations.
Why, like Mr Flynn, did Mr Sessions tell a stupid and reckless lie that was bound to be discovered and exposed? What is the Trump team hiding about their connections to Russia?
Could this be a cover-up without any underlying scandal? Does that ever happen? Is it all just rank stupidity, and Mr Trump’s inexplicable infatuation with Vladimir Putin just a coincidence?
It’s always possible, but looking increasingly less plausible. Whenever, as now, a White House is pressuring the FBI not to investigate something, every alarm bell shrieks.
Very few facts are known, but a pattern is emerging: for whatever reason this administration is engaged in a Nixonian stonewalling and denial effort, increasingly reminiscent of Watergate, no less. If any underlying scandal is indeed connected to efforts to influence the election by a hostile foreign power, it will be an even bigger earthquake.
Richard Nixon was somewhat immunised by his clownish, fuming vice president, Spiro Agnew. Anyone considering removing Nixon had to take seriously the prospect and consequences of facilitating the emergence of a President Agnew. It gave them pause.
Agnew’s guilty plea on corruption charges was a significant blow to Nixon. So was Agnew’s replacement by Gerald Ford, who was widely considered plausible, though hardly ideal, presidential material.
Just as the spectre of Agnew bought Nixon some precious political space and time, now the looming shadow of Mr Pence may start to haunt Mr Trump.
The conventional wisdom is that Mr Trump is protected from any effective oversight by the Republican-dominated Congress because he seems willing to sign much of their legislation, nominate judges they like and cooperate on some things.
However, many congressional Republicans still harbour private doubts.
The only major tenet of traditional American conservatism Mr Trump truly embraces is deregulation. Regarding almost all other once-core Republican principles, such as small government, budget hawkishness and entitlement rollbacks, social conservatism, and robust international leadership, he either isn’t interested or is actively hostile. Mr Trump’s recent address to Congress reflected none of these ideas.
Mr Pence, by contrast, is a traditional conservative Republican. His politics reflect the Reagan legacy, not the populist “nationalism” of Breitbart.com.
Moreover, as unsettling as Mr Trump has been as president, Mr Pence has proven reassuring, and, perhaps surprisingly, statesmanlike, as vice president. Despite his doctrinaire Republican background, he has been among the more calming features of the administration, a welcome vestige of American political normality, however conservative, in profoundly abnormal circumstances.
Republicans, particularly in Congress, have made little real progress in ensuring that Mr Trump embraces their governing agenda rather than his wildly divergent campaign pledges.
If the Trump-Russia imbroglio continues to develop, as seems likely, and significantly undermines Mr Trump’s credibility and legitimacy as president, congressional Republicans will be faced with a very difficult choice.
Getting rid of a president from their own party would certainly be painful and difficult.
However, when the alternative is a familiar, trusted figure Mr Pence, who could be counted on to return the party, government and agenda to a more familiar conservative approach, rather than Mr Trump’s wild-eyed nativism, that very bitter pill may have a sugary coating.
They may not relish the required process, but how many conservative Republicans in Congress wouldn’t, in their heart of hearts, much prefer to work with a president Pence instead of president Trump? It’s a question they may have to ask themselves sooner rather than later. Some of them, very quietly, already are.
Hussein Ibish is a senior resident scholar at the Arab Gulf States Institute in Washington
On Twitter: @ibishblog