It’s just one poll, and even if other polls next week confirm the trend, you know the cardinal rule about Trump’s approval. Come rain or shine, be it winter, spring, summer, or fall, his numbers never move very far from 43 percent for very long. He might take a short-term hit in his polling thanks to the obstruction material in Mueller’s report. He might even take a medium-term hit once Mueller ends up in front of House committees and starts testifying in person about instances of Trump’s misconduct. But long-term?

Forty-three percent. It’s practically the fourth law of thermodynamics.

It’s worth noting that Trump did get a small bounce from Bill Barr’s summary of Mueller’s report late last month. His approval rating had been declining steadily in March, from 44.2 percent at the start of the month in RCP’s poll of polls to 42.2 shortly before Barr’s summary was published. It began rising immediately afterwards and now has settled back in at 43.9. Rarely do current events affect his numbers but Mueller and Russiagate apparently have enough weight to move them a little. Maybe in both directions:

According to the poll, 37 percent of adults in the United States approved of Trump’s performance in office, down from 40 percent in a similar poll conducted on April 15 and matching the lowest level of the year. That is also down from 43 percent in a poll conducted shortly after U.S. Attorney General William Barr circulated a summary of the report in March…

Among those respondents who said they were familiar with the Mueller report, 70 percent said the report had not changed their view of Trump or Russia’s involvement in the U.S. presidential race. Only 15 percent said they had learned something that changed their view of Trump or the Russia investigation, and a majority of those respondents said they were now more likely to believe that “Trump or someone close to him broke the law.”

The poll was conducted beginning on Thursday afternoon, in the first hours after the report was published, through Friday morning. That is, this is very much a “snap judgment” measurement. Maybe the numbers will have changed a week from now after people have had more time to digest Mueller’s findings, although in which way is anyone’s guess. Given the crush of media commentary about how damning the obstruction section is, it’s possible his approval will drop further — again, short-term, not long-term.

The most interesting result in the crosstabs are the answers to the question, “[H]ave you learned anything so far from the report that has changed your mind about the Trump campaign and/or Russia’s involvement in the presidential race?” Only 15 percent said yes, but that’s a not insignificant number with the next presidential campaign already under way. That 15 percent wasn’t all Democrats either: 18 percent of Republicans and 11 percent of independents answered affirmatively. And among those who did, overwhelmingly they said that the new information they’ve learned has made them more likely, not less, to believe that Trump or someone close to him broke the law — 72 percent of Dems, 68 percent of Republicans, and 67 percent of independents.

Do the math there and you find that something like seven percent of all independents are now more suspicious of Trump and his inner circle post-Mueller. (Roughly two to three percent are less suspicious.) Trump won independents by four points in 2016. *If* voters have long memories about this, it really could a problem him next fall.

But voters tend not to have long memories. And despite the greater misgivings about Trump after Mueller’s report, the impeachment numbers are still on his side. Those are moving in the wrong direction too, from 39/49 last month in favor of impeachment to 40/42 yesterday, but that’s still a long ways away from what Democrats would want to see before they pull the trigger. You don’t impeach the president when the public’s evenly split, you impeach him only when it’s overwhelmingly supportive — and if Mueller’s report hasn’t made Americans overwhelmingly supportive, nothing will. The numbers just aren’t there, notes Nate Silver, not in this poll and not in others:

Furthermore, people who voted in the midterms also opposed impeachment by a wide margin (39-56 in the national exit poll). pic.twitter.com/lgcHhayezP

— Nate Silver (@NateSilver538) April 19, 2019

Democrats surely have every right to make their case for impeachment and seek to persuade the public. But right now, ~55% of voters oppose impeachment, even though only ~40% approve Trump. In a democracy, IMO it's not just politically wise but *normatively* wise to consider that.

— Nate Silver (@NateSilver538) April 20, 2019

Can’t undo the results of a national election because ~40 percent of the public thinks it’s a good idea. And yet some liberals who’ve spent the past two years pointing to the popular vote as evidence that the public’s will was thwarted in 2016 seem willing to thwart the public’s will themselves on impeachment.

By the way, this isn’t quite the only poll out there to show a decline in Trump’s approval since the report came out. YouGov’s tracking poll had Trump at 43 percent on Monday and Tuesday, 42 percent on Tuesday-Wednesday, 41 percent on Wednesday-Thursday, and then 40 percent on Thursday-Friday, after the report was finally released. Obviously not all of that is a reaction to Mueller’s findings, but that’s another data point to watch next week. Or tomorrow, since it’s likely that some of the big pollsters are preparing to release their own “snap judgment” data on the Mueller report in time for the Sunday shows.