So much had been trailed in advance of James Comey’s over-hyped interview on ABC News at the weekend that when it actually aired there wasn’t much left to surprise me beyond the over-edited woodenness of the whole thing. Instead of visceral, Comey came across as viscous.

Still, I did stick with it. I may yet read the book that formally hit the shelves on Tuesday. How often do you have a just-fired FBI director calling the sitting president “morally unfit” for office or speculating that the oddly pale hue of the bags under his eyes must come from wearing goggles on his tanning bed. (Did he have one installed in the White House? Where is it plugged in?)

Yet, one thing did grab my attention. Having spent the best part of the hour with George Stephanopoulos explaining his disdain for Trump, he then posited that those who want him impeached are barking up the wrong tree. Pardon, what? If Trump is so rotten, so unable to separate lies from the truth, shouldn’t the country get rid of him at the earliest opportunity?

Let’s remember first that talk of impeachment is very much alive and well. Though the most recent polls have shown a slight narrowing of the advantage that Democrats hold going into the crucial midterm elections this November, it still seems more likely than not that they will wrest control of the House of Representatives from the Republicans. Conceivably the Senate too.

The Republicans are under no illusions about the peril they face. When the speaker of the house himself, Paul Ryan, announces months in advance that he won’t be running for re-election you know things must be dire. You don’t flee before you’re sure your goose is cooked.

Regaining the majority in the lower chamber would free the Democrats to approve articles of impeachment against Trump. That was the fate of Bill Clinton at the end of 1998 after he had been hounded for years by a special prosecutor. The Democrat majority in the Senate meant he kept this job. So Trump had better hope the Senate doesn’t fall into enemy hands too.

But the cogs of impeachment are big and scary. Once they start grinding, the whole country begins to shudder and shake. Nothing else of any great significance gets done on Capitol Hill. Voter polarisation worsens. So how wise would it be to engage them, really?

Tom Steyer speaks during the 'People's State of the Union' event one day ahead of Donald Trump's State of The Union Speech to Congress, in Manhattan, New York (REUTERS/Darren Ornitz)

No one aches for it more than Tom Steyer, the billionaire environmental philanthropist who to Democrats is what the Koch brothers are to Republicans. Nowadays he is singularly focused on on making impeachment happen. More than 5 million have signed up to his Need-to-Impeach petition and he has burned cash running TV ads all over the land making his dump-Trump pitch. In a couple of weeks he starts a series of townhall-style meetings in Iowa, the state that always has an outsized role, in part to pressure David Loebsack, an Iowa congressmen who was the only Democrat not to support a non-binding impeachment resolution earlier this year.

“Those who condemn Trump but do not back their words with action are enabling the damage he is inflicting on our country,” Steyer said this week. “Representative Loebsack should explain why he is acting against his constituents’ wishes by voting no on impeachment. The people of Iowa deserve elected leaders who refuse to back down on our shared principles.”

Does the Democrat leadership love Steyer for devoting himself to the issue? No, they really do not, because they know it could sow dangerous division in their own ranks in the run-up to November. The activist wing of the party and members of Resist would be fired up, but more moderate Democrats as well as Independents who might otherwise be infuriated by Trump and whose support they need will find the prospect of an impeachment fight thoroughly unappealing.

In the meantime, if impeachment is a central plank of the Democratic platform Republicans would find themselves with an unexpected opportunity to energise their base. They’d call them to the ramparts to prevent what they will characterise as an approaching coup. Fundraising for their candidates could go through the roof and so might Republican turnout on election day.

That’s a summary of why the Steyer path may not be strategically smart. But the Comey case is different and altogether more interesting. In 2016, America committed a form of self-harm when it chose Trump over Hillary Clinton. Razoring itself at the ballot box. To understand and to heal, voters must make the difficult and steep journey out of that bad place all by themselves.

To get rid of Trump through impeachment would let them “off the hook”, he offered. “People in this country need to stand up and go to the voting booth and vote their values. You cannot have, as president of the United States, someone who does not reflect the values that I believe Republicans treasure and Democrats treasure and Independents treasure. That is the core of this country. That’s our foundation. And so impeachment, in a way, would short circuit that.”