In recent days, President Donald Trump has escalated his assaults on the “Fake News” media and other institutions, in an increasingly frantic effort to carve out a kind of safe space that cannot be penetrated by accountability or factual reality. Inside this bubble, the truth is what Trump says it is, on Twitter and in his tirades before rally crowds, where Twitter replies (even by bots) and raucous cheers serve as confirmation of Trump’s versions of events in a kind of intensifying feedback loop.

But if the brutal new poll released Tuesday by CNN is any indication, that safe space seems perilously small.

Trump’s own advisers appear to believe his safe space is shrinking. As The Associated Press reports Tuesday, this is what explains his recent antics:

“The president has increased his media-bashing via Twitter and staged rallies hoping to marshal his base to his defense. … There are signs that his support among Republicans may be softening. His advisers are aware that a serious slip in support among his core voters could jeopardize hopes for a major, early legislative accomplishment and would certainly increase Republicans’ worries about his re-election prospects.”

Tuesday’s CNN poll confirms that Trump’s support is shrinking. It finds that his approval is down to 38 percent, with 56 percent disapproval. Only 37 percent say he has the right priorities, while 59 percent say he hasn’t paid attention to the country’s most important problems. Americans say by only 43 percent to 55 percent that he can bring the change the country needs.

But more interesting, perhaps, is what the CNN poll tells us about his overall communications strategy:

55 percent say Trump has lowered the stature of the presidency, while only 17 percent say he has raised it, and another 25 percent say it is unchanged.

Only 31 percent say Trump’s actions have made them more confident in his ability to serve as president, while a staggering 62 percent say they’ve left respondents less confident.

A total of 73 percent have low trust in what they hear in official communications from the White House: 30 percent trust nothing at all, and 43 percent trust just some of it, while 19 percent trust most of it and 5 percent trust almost all of it — meaning only 24 percent trust what this White House tells them.

Meanwhile, the CNN poll finds broad discomfort with Trump’s use of Twitter. A large majority says Twitter does allow Trump to communicate directly, but few Americans think this is a good thing:

“A majority (52 percent) say his tweets are not an effective way for him to share his views on important issues, and 72 percent say they do not send the right message to other world leaders.

“Seven in 10 say they too often seem to be in response to TV news the President may have seen, and 71 percent that they are a risky way for a president to communicate. Six in 10 say they are easy to misunderstand, 63 percent that they too often turn out to be misleading.”

Trump’s operating premise has been that he can scramble the political calculus with his unconventional, disruptive communications approach, which involves using social media and rallies to communicate directly with the American people, while bludgeoning the credibility of institutional sources that are providing information that undercuts his “alternative facts.” This probably helped him get to the White House.

But now that Trump has tried to bring this strategy to governing, here’s the result: Only small minorities believe what the White House is telling them; and thanks in part to his nonstop antics, majorities lack confidence in his ability to serve and believe he has degraded the presidency.

Trump’s gut-level calculation seems to be that his long-term political survival depends on forging an enduring bond with his supporters — a bond that appears dependent on delegitimizing (in their minds) all outside sources of information. The probe into Russian sabotage of our election, which our intelligence services have documented, is nothing but a hoax. Reporting that fills in details about the ongoing Russia probes, or raises doubts about his fitness for the presidency (such as that crazy conversation with the Australian prime minister), are dismissed as “fake news,” before subsequently being confirmed. As CNN’s Jake Tapper put it: “Almost every single time he’s used that term, the news has been accurate. It’s just been news he doesn’t like.”

Indeed, Trump’s use of “Fake News” is even broader than this: It is also a catchall dismissal, a forward-looking one, that seems to be designed to prep his supporters to dismiss future revelations that likely will be forthcoming as special counsel Robert Mueller’s probe intensifies. It is part of a broader effort to delegitimize in advance the institutions that will likely escalate their efforts in coming weeks and months to hold him accountable.

But this appears to be further alienating the large majorities outside his safe space — and that safe space seems to be shrinking.

Greg Sargent writes The Plum Line blog for The Washington Post.