WASHINGTON -- In the normal course of events, the successful demagogue demands and receives cringing deference. But how about a little empathy now and then?

Everyone loves heroic dissidents like Sir Thomas More, at least when canonizing them has no cost. They get all the best press and plays about them. Yet who stops to consider the predicament of the prince? He can always find some lickspittles who will do as they are told. But the problem with lickspittles is their darned undependability. Men or women who are subservient out of self-interest will turn against the prince when their interests change, or when they get a plea deal. One day they are drinking at a prince's open bar. The next they are talking to "60 Minutes" or congressional investigators. No matter how much the Michael Cohens of the world are favored and rewarded, their allegiance will go with a better bid.

Deep down -- at their most honest and vulnerable -- what demagogues really want is sycophants who act out of conviction. Is it too much to ask for servants who grovel because they really mean it?

By this standard, Donald Trump must be a very happy man. In Attorney General William Barr, he has finally found someone who licks his boots out of principle.

Barr was clearly chosen for his position because he genuinely believes in expansive executive authority. But his performance Wednesday before the Senate Judiciary Committee went a step further. Barr made an argument for expansive and largely unaccountable executive authority.

The attorney general essentially argued that if a president really, really, really believes he is innocent of a crime, then he can undermine an investigation of that crime without the "corrupt motive" required to prove obstruction of justice. Said Barr: "If the president is being falsely accused -- which the evidence now suggests that the accusations against him were false -- and he knew they were false, and he felt that this investigation was unfair, propelled by his political opponents, and was hampering his ability to govern, that is not a corrupt motive for replacing an independent counsel."

This is a remarkable claim on several counts. The Mueller report does not provide evidence that the accusations against Trump were false. It found that the evidence was not sufficient to prove a criminal conspiracy. If the accusation is that the Trump campaign had extensive, disturbing contacts with a hostile foreign power in an attempt to gain political advantage, then the Mueller report comprehensively proves the charge. This tendency by Barr to equate the absence of a crime with vindication for the president is what makes him sound like part of Trump's defense team. It is also what seems to have rubbed special counsel Robert Mueller the wrong way, provoking his "snitty" letter of protest to Barr.

It is the broader implications of Barr's view of obstruction, however, that should concern us the most. He is claiming that Trump's belief in his own innocence, along with his conviction that political opponents were out to get him, constituted a sufficiently pure motive to fire Mueller (and much else) without incurring the guilt of obstruction of justice. But what president -- Richard Nixon included -- does not believe in his own innocence until a smoking gun appears? What president does not believe that his opponents are unfairly accusing him? And how should an attorney general determine that such beliefs are sincerely held?

The standard that Barr sets essentially makes obstruction of justice by a president impossible to demonstrate. And this amounts, for a president such as Trump, to preemptive permission.

I have no doubt that Barr believes his own argument. But this is what should please Trump the most. Barr is not merely summarizing Mueller's findings. He is providing justification for Trump's whole approach to the Mueller investigation -- the president's charge of a "witch hunt," his raging paranoia, his belief that everyone who serves at his pleasure should do his bidding. Barr is bowing and scraping with complete sincerity. Finally, Trump has found a man of integrity to bless his corruption.

Does this mean that Barr should resign as attorney general? He has diminished the independence of his office, not just in fact but in theory. He has removed a check on presidential power within the executive branch. This does damage to the effectiveness and standing of federal law enforcement.

But Barr, by his own lights, is performing his duty. And his boss has every reason for satisfaction. Why begrudge a prince his fondest wish?

(c) 2019, Washington Post Writers Group