On Monday, Nate Cohn, The New York Times number-cruncher, published his latest analysis of public opinion about the impeachment inquiry currently underway in the House. He's written several. This time, Cohn looked at how people in key swing-states view the process, according to a survey conducted by The Times and Siena College. As it is in all such articles, he found "a deeply divided electorate," with "the president’s core supporters and opponents exceptionally energized and unified."

My reaction to the piece--and others like it--is that it's way too early to draw any conclusions from where the public stands on removing Trump. Speaker Nancy Pelosi formally kicked off the inquiry 27 days ago and since then, a grand total of one person, acting director of national intelligence Joseph Maguire, has offered public testimony related to the probe.

At this early stage, the trend seems far more significant than what the polls may say about the public's mood at present. When Pelosi made the announcement, 39 percent of respondents favored impeaching Trump and 51 percent of them opposed it, according to FiveThirtyEight's average. Now, less than four weeks later, impeachment enjoys plurality support, at 49-43. That's a huge shift in a short period.

It's become common to reference how far opinion moved during the Watergate hearings. Richard Nixon's approval rating was in positive territory a month before the hearings began and shortly after, fewer than one-in-five Americans told Gallup that they favored his removal from office. By the time Nixon resigned in disgrace a year later, support for impeachment was at 57 percent and only a quarter of respondents said they still had a favorable view of Tricky Dick.

But there's a counter-argument: The fact is that while Trump is the fourth President* to face the prospect of impeachment, there is really no historical precedent to guide us.

Nixon was the closest parallel. His crimes--especially his attempts to obstruct an FBI investigation into his associates and relentless efforts to block Congressional oversight--were the most similar. But that was during the post-World War II era of "liberal consensus," when there was quite a lot of ideological overlap between the parties and far less negative partisanship.

More importantly, the Watergate Hearings took place before the advent of right-wing talk radio, Fox News and the rest of the conservative media apparatus.  People disagreed back then, but they shared a common set of facts. Everyone watched Walter Cronkite read the news at 6 pm.

According to the latest WSJ/NBC poll, it's a safe bet that Nixon would have served out his second term in this bifurcated media environment...

Fewer than 30 percent of Americans who get their news via broadcast TV, CNN or MSNBC believe Trump has been honest about the Russia probe, compared with 61 percent of Fox News viewers.

Just a sliver of broadcast/CNN/MSNBC viewers say the Mueller report cleared Trump of wrongdoing, versus 50 percent of Fox News watchers.

And fewer than 40 percent of those who consume their news via broadcast TV, CNN or MSNBC approve of Trump’s job performance, compared with 73 percent who get their news from Fox.

Bill Clinton went through the process in a highly polarized environment that was much like our own, but that was for lying about sex, something that most adults have done at one point or another. He was also very popular at the time, with an approval rating in Gallup's polling that had never dropped below 60 percent during the first 11 months of that year--and reached as high as 69 percent at one point. Trump's accused of serious crimes, and has been under water in FiveThirtyEight's polling average ever since his 15th day in office.

Obviously, we were still communicating via the telegraph when Andrew Johnson was impeached in 1868. That was related to tensions surrounding Reconstruction following the Civil War. Women didn't have the right to vote, and men of color enjoyed it in theory but not in practice in many parts of the country. A different era entirely.

I tend to cling to the idea that the normal rules of politics still apply, at least to a degree. I think that if evidence of Trump's crimes becomes too great for Republican elites to defend, they will still turn on him, giving permission to all but the most die-hard Trump cultists within the GOP base to follow suit. But we just don't know. And in this case, history just isn't much of a guide.