Let us praise Robert Mueller.

We don't know precisely what's in the report the special counsel delivered this week to the Department of Justice, but it seems possible it will contain neither the full-throated condemnation of President Trump that critics want — there are reports Mueller has recommended no further indictments — nor the clean-sweep exoneration that many MAGA-minded citizens have been demanding from the beginning. There's a real chance that after nearly two years of investigation into the Trump administration's links to Russia, everybody's going to be at least a little bit mad.

So why praise him?

Because the public evidence suggests that in his stint as special counsel, Mueller has been an exemplary public servant.

He has been effective, getting indictments, convictions or guilty pleas from 34 people and three companies. He has been efficient, wrapping up his investigation in under two years when previous inquiries into Whitewater and the Iran-Contra scandal went six years or longer. And he has run a tight ship, keeping his operation largely leak-free despite operating under intense scrutiny. In the midst of a political carnival, Mueller and his team put their heads down and did their jobs, building cases instead of their own celebrity.

What's more, they did so in the face of incredible opposition: A president — Mueller's boss, by the way — and a television network that dedicated themselves to delegitimizing and undermining the investigation. (This doesn't even count members of Congress, like Rep. Devin Nunes (R-Calif.), who used the power of their offices to apparently run interference for the campaign.)

To a lesser extent, Mueller has also had to cope with the hopes of many Democrats and liberals — I confess I was one of them — who believed he would find a smoking gun that would bring the Trump presidency to an end.

There were expectations and anger on every side of this investigation, in other words. If it affected Mueller, he didn't let it show.

Such steadiness is what we should expect from a public servant. But it took on added significance in this particular case: Mueller was investigating a president who is more entertainer than statesman, a fickle man who turns everything around him into chaos, who feeds off grievance and needs an enemy to attack — if it hadn't been Mueller these last two years, it almost certainly would've been someone else.

But Mueller has not played the villainous role the president tried to assign him. In his bearing, persistence, and simple ability to keep his mouth shut, the special counsel has proven to be one of the few figures in public life — Nancy Pelosi might be the other — who hasn't been sucked into Trump's way of doing things.

It's instructive to compare Mueller to Ken Starr, the Whitewater prosecutor who allowed the investigation into Arkansas land deals to turn into an impeachment about sex, and who even now — 20 years later — seems to be chasing every television camera that will let him ruminate on the Russia investigation. Or contrast Mueller with James Comey, the former FBI director and material witness in the Russia investigation, who took a book deal and keeps playing pundit when he should stay quiet.

The coming days and weeks will no doubt reveal some imperfections in Mueller's efforts. Why wasn't Donald Trump Jr. indicted? Why did prosecutors cooperate with targets like Michael Flynn and Michael Cohen if there weren't bigger fish to fry? Lots of questions remain unanswered. My colleague Ryan Cooper is correct: The full Mueller report must be made public.

What we may find out, though, is that Mueller has done his job: Now it is time for members of the House and Senate to do theirs. Thanks to the special counsel investigation, we know the president has surrounded himself — during his campaign and his administration — with men who are willing to cheat and lie to advance both their interest and Trump's. Robert Mueller's investigation has already given us a roadmap to this presidency's criminality. For that, Mueller deserves the thanks of a grateful nation.

He did his duty. Will Congress?