Sean Spicer helped get the year off to an untruthful start. (Jabin Botsford)

Media columnist

On Jan. 22, Kellyanne Conway defended the president's order that Sean Spicer, in his first appearance before the White House press corps, should feed reporters a whopping lie.

Spicer wasn't really wrong about the inauguration crowd size when he said it was the largest in history, Conway insisted to NBC's Chuck Todd.

No, he was merely using "alternative facts."

A lot has happened since then — a daily tsunami of mind-numbing craziness — but try to remember how insane this sounded at the time.

And think about where we are now.

Then you will know why, as 2017 unfolded, I started saying "reality-based press" to describe what detractors prefer to call the mainstream media. President Trump, of course, takes the disparagement further, referring to "fake media" in his constant effort to undermine reporting that isn't pure adulation.

I use the phrase because journalism has one essential job: to dig out and communicate the facts — yes, actual facts — about what powerful individuals and institutions are doing. And to hold them accountable through that fact-based reality.

Granted, we don't do it flawlessly. And there are plenty of critics who jump on mistakes and claim that they invalidate everything else that is reported.

But consider some of what American citizens wouldn't have known if not for journalists rigorously doing their jobs this year:

● That retired Lt. Gen. Michael Flynn, Trump's former national security adviser, lied about his pre-inaugural contacts with Russian Ambassador Sergey Kislyak. (Trump defended Flynn staunchly after The Washington Post reported on this in February — right up until the time that he fired him.)

● That Hollywood producer Harvey Weinstein allegedly preyed on vulnerable women for decades. (Weinstein, who still denies credible charges of sexual harassment and assault, portrayed himself as a great benefactor of women in the entertainment industry. It took dogged reporting by the New York Times and the New Yorker to show that the opposite was true.)

● That Alabama Senate candidate Roy Moore, as a man in his 30s, allegedly sought romantic relationships with teenage girls, and in one case, allegedly had sexual contact with a 14-year-old girl. (Moore, who lost, continues to deny wrongdoing — or even knowing those who told their experiences in The Post and elsewhere.)

● That the death toll in Puerto Rico, months after Hurricane Maria, appears to be over 1,000. (The official count by the government is only 64; but reporting by the island's Center for Investigative Journalism and the Times document the higher numbers.)

That's the reality-based press at work. Now we've entered a troubling new level of opposition to it and what it stands for.

It's led by Fox News (which, though it can be called mainstream, cannot consistently be counted as part of the reality-based press), in league with Trump and, increasingly, many Republicans in Congress. They are building a case, day after day, that special counsel Robert S. Mueller III — a Republican known for his strait-laced integrity — is out to destroy the Trump presidency for partisan reasons.

"We have a coup on our hands in America," as Fox host Jesse Watters claimed last weekend. That's only a slightly more eye-popping version of what Tucker Carlson and Sean Hannity have been saying nightly on their Fox shows.

Then, taking this a vile step further, a paid Fox contributor, Kevin Jackson, on Tuesday floated the conspiracy theory that the FBI might have had plans to assassinate Trump. Par for the course: Earlier this month, Jackson blithely claimed on Fox that Trump had released his tax returns, a straight-up lie.

The author Yascha Mounk wrote recently that while politicians have always lied and exaggerated, what's happening now is something new.

"The construction of an alternate reality that obviates the very possibility of conducting politics on the basis of truth is a novelty in this country," he said in a New York Times op-ed. "And it is increasingly becoming obvious that it will serve a clear purpose: to prepare the ground for egregious violations of basic democratic norms."

I'm afraid he's right. And everyone who cares about American democracy should be on guard.

What's mildly encouraging amid all this is that reality seems to be getting through to people. For example, despite the relentless salesmanship about the newly approved tax overhaul, ordinary Americans understand that it is not meant primarily for their good but rather to benefit the wealthy and corporations: It's vastly unpopular.

So it may be useful to remind people regularly that there is a clear difference between truth and propaganda, between fact and falsehood.

And that journalists in the reality-based press are on the saving side — if there is one — of that increasingly dangerous divide.

For more by Margaret Sullivan visit wapo.st/sullivan