Now that Justice Ruth Bader Ginsburg has taken herself to the woodshed, it’s worth asking what her brief bout of Trump Derangement Syndrome says about our system’s ability to withstand four years of a Trump presidency.

Short answer: It is not a good omen.

As the idea of a President Trump has evolved from laughable to unlikely to oh-my-god-this-might-actually-happen, a debate has raged in Washington.

The debate is not over the man’s fitness for office — few people privately will make the case that Donald Trump is qualified or temperamentally suitable to be commander in chief — but over how much damage he might do.

Some say that Trump could be more disruptive than any previous leader, including propelling the nation toward fascism.

The Notorious RBG isn’t backing down from her negative comments about Republican presidential candidate Donald Trump, and now he’s calling for her resignation from the Supreme Court. Here’s a quick rundown of what the two have said. (Jenny Starrs/The Washington Post)

But an anti-alarmist caucus responds that the U.S. system is stronger than any single person — that we could rely on the Constitution, on long-established checks and balances, on watchdogs in the press and elsewhere, and on leaders who would stand up for the rule of law.

For example, Trump has endorsed the torture of terrorism suspects and the punitive bombing of their innocent families. But if he tried to implement such illegal measures, the reassurers argue, military officers and civilian bureaucrats would refuse to obey. If he tried to round up and deport 11 million people without due process, judges would object. Congress, too, would check executive overreach.

I would like to believe this argument, but a time like this brings home how much the U.S. system relies not just on laws but also on habits of abiding by them: on an ingrained respect for norms, for democratic give-and-take and for civility.

That respect has been ebbing in recent years as partisanship has grown more poisonous. Republicans would argue that President Obama has pushed the envelope with executive orders that have ignored congressional intent and undercut the separation of powers.

But when judges declared that Obama had gone too far with his attempt to legalize millions of illegal immigrants, he stood down. He was bitterly disappointed, no doubt, but acceded to the judicial decision.

What if a president decided to ignore such a decision? What if he had appointed an attorney general, a budget director, a border chief or other bureaucrats eager to abet such defiance?

Imagine, for example, that judges told a President Trump that he could not turn the Southwest border region into “a police state,” which the executive director of the American Civil Liberties Union forecast in a recent Post op-ed would be the result of Trump’s plan to deport 11 million undocumented immigrants. Imagine that Trump and his administration continued building camps anyway. Given the contempt that Trump has expressed for the judiciary, and the ignorance he has displayed of the Constitution, that scenario is not so far-fetched.

At such a moment, laws could not save you; only people could. Would members of Congress, career civil servants and others stand up to Trump and for the rule of law — and could they oppose him while remaining true to principle and not descending to his level?

On the first question, the evidence from Trump’s party is not encouraging. Republicans who months ago were clear about the danger that he represents have abjectly fallen into line, albeit with varying levels of enthusiasm. If House Speaker Paul D. Ryan (R-Wis.) cannot disavow a candidate he has accused of racism, why would we think he would be firmer when that espouser of racism lived in the White House?

The second question — could Trump’s opponents stay true to their own values? — is where the Ginsburg episode is discouraging. Like Sen. Marco Rubio (R-Fla.), with his playground taunts during primary season, Ginsburg let Trump drive her to behavior she must on some level have known was wrong, tactically as well as ethically.

The derangement is understandable. Trump is corrected by fact-checkers but just restates his fictions more loudly. He insults war heroes and pays no apparent price with veterans. Lies, conspiratorial insinuations, name-calling and behavior that would knock most candidates out of contention — concealing his tax returns, for instance — do not appear to harm him.

How to respond? If you pretend, as Ryan has, that Trump is an ordinary Republican leader, just one speech away from acceptability, you end up looking like a sap.

So the temptation is to match insult with insult, or (as some protesters did during primary season) violence with violence.

But engaging Trump at the insult game only reinforces his implicit argument that the talents of a reality-television star are sufficient for a president. And a judge embracing partisanship and abandoning judiciousness reinforces another cynical Trump view: that the system is “rigged” and all our leaders are dumb or venal.

Trump brought the worst out in Rubio and Ginsburg. What will it look like if he draws out the worst in our country?

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