For governments to function amid deep disagreements between their major players, they sometimes evolve shared understandings. Their premise is that in some conflicts, preserving the integrity of the system, and its fidelity to serving the public, must take priority over pursuing political Total War all the way down.

One such understanding might be that if one party’s leader and his co-conspirators try to overturn a legitimate election with mob violence, a broad cross-party effort at accountability must follow. Another might be that Congress has legitimate oversight powers, and that while some resistance to this is within bounds, absolute resistance to it is not.

A vile new attack from House Minority Leader Kevin McCarthy (R-Calif.) on Rep. Liz Cheney (R-Wyo.), and Stephen K. Bannon’s flouting of a subpoena from the House select committee investigating Jan. 6, both underscore the fragility of such shared understandings.

In so doing, both episodes demonstrate once again just how dangerous a GOP-controlled House might truly prove to be.

The New York Times reports that a prominent lobbyist and longtime McCarthy confidant has essentially delivered a message to GOP consultants inclined to work for Cheney that would shock the most inventive “Sopranos” scriptwriter: Nice consulting practice you have there. Shame if something happened to it.

The McCarthy consigliere told consultants to choose between working for Cheney and working for McCarthy, the Times reports. With McCarthy potentially the next House speaker, consultants must take such threats seriously, so one firm working for Cheney severed their relationship.

This threat surely had McCarthy’s assent. Importantly, McCarthy has good reason for assenting: Cheney’s high-profile participation in holding Donald Trump accountable for the insurrection and effort to subvert the election, which will implicate House Republicans, shines a harsh light on GOP radicalization, threatening the GOP’s midterm chances.

It’s typical for party leaders to exercise discipline with hardball tactics. But Daniel Ziblatt, co-author of “How Democracies Die,” notes a key nuance: What’s being enforced entails punishment for seeking accountability for the elite overseers of anti-democratic street violence and an effort to disrupt democracy at its foundation.

“It’s not as if they’re enforcing this party discipline over Cheney on a tax bill,” Ziblatt told me. Remember: McCarthy also openly threatened that a GOP majority would punish private companies that cooperate with the Jan. 6 probe.

“This is how democracies get into trouble,” Ziblatt said. “It’s not just violence in the streets, it’s how the establishment responds.”

Bannon and ‘executive privilege’

Meanwhile, all but nine House Republicans voted against holding Bannon in contempt for defying the select committee’s subpoena. Democrats believe Bannon can illuminate Trump World’s potential understanding of their scheme as a deliberate plot to overturn an election through intentional procedural corruption and/or violence.

Most House Republicans do not want that to be illuminated. And they appear okay with Bannon defying a lawful subpoena to keep it buried. It’s ominous that virtually the entire GOP conference, and McCarthy himself, declared Bannon beyond accountability on this matter.

Bannon’s argument for defiance is specious: His lawyer claims he is honoring Trump’s demand that communications with advisers be protected from the committee by “executive privilege,” but Bannon was a private citizen throughout the time in question.

Note that “executive privilege” is also a place where shared understandings help make governments function. When presidents invoke executive privilege to resist congressional oversight, what has traditionally happened is the two sides reach negotiated settlements.

The core idea here is that there will be push and pull, but ultimately resistance to congressional oversight shouldn’t be absolute, that at some point, presidents need to cooperate with it to make the system work for the public.

But Trump’s idea is that he can invoke executive privilege as a former president, to protect himself against accountability for trying to disrupt the system at its very roots. As the current White House counsel notes, this is dubious as it serves no conceivable public interest. Yet virtually the entire House GOP is siding with Trump.

How long a leap?

Here’s the question: How long a migration is it from this bad acting — from wielding horse-head-in-the-bed threats to discourage an accounting into an effort to overthrow democracy and protecting its architects — to using a House GOP majority to help subvert a future presidential election?

We don’t know whether a House GOP majority would count rogue presidential electors sent by a GOP-controlled state legislature in defiance of its popular vote, or whether it would unleash some other similar constitutional nightmare.

But shouldn’t we ask how big a leap it is from here to there? What else is a House majority controlled by these bad actors truly capable of?

All this ups the stakes for Democrats. As Brian Beutler notes, if the Justice Department determines that prosecuting Bannon for defying the subpoena is the lawful course of action, yet refrains out of fear that this would inevitably lead to confrontation with Trump, it will signal that naked subversion of the rule of law is without consequence and beyond accountability entirely.

The specter of such a GOP majority should also prompt Democrats to revise the Electoral Count Act and pursue other democracy-protecting reforms — and end the filibuster if necessary to do so.

When the shared understandings that undergird democratic stability erode to the point of implosion, sometimes only the proper and judicious use of power will suffice to guarantee that stability endures.