A trigger warning at the outset: This article relies on polls. If your reaction to that is something like “but the polls were wrong last year about Trump and therefore this should be ignored!!,” that is, of course your prerogative. That said, Trump led in national primary polling for every single day save two from July 2015 through his nomination. General election polling had him consistently down nationally, and he lost the popular vote by 1.1 fewer points than polling averages indicated.

If Donald Trump wants to be worried about anything — and his Twitter feed of late indicates that he does — he might want to begin with his political base of support.

It’s early both in terms of Trump’s presidency and of a trend of Trump’s base eroding, but, as we all know, it’s better to accept and confront problems early instead of pretending they don’t exist. So while two polls released this week aren’t dead canaries in the coal mine, someone might want to take these canaries to the vet.

A new Associated Press-NORC poll released on Thursday shows that most Americans disapprove of Trump’s performance as president. That’s not new. What’s new is that the AP shows a big drop in Trump’s net approval rating, that is, the percent who approve of the job he’s doing minus those who don’t. In March, Trump’s net approval was minus-16. Now it’s nearly twice as big.

We’ve also seen huge disapproval numbers from Democrats before. But Trump’s approval among Republicans is only 75 percent, a significantly lower figure than we’ve seen in other polls. This is one poll, and we should never try to build a broad case on one poll. But there’s other evidence at hand.

For example: Since March, the percentage of Americans who approve of Trump’s handling of key political issues has slipped across the board. That includes on the economy, an issue which Trump has repeatedly indicated is his core strength and the metric by which he should be judged. In March, half the country approved of his handling of the economy. In the new poll, that’s fallen to 43 percent.

Meanwhile, Gallup released new monthly numbers on America’s satisfaction with the way things are going in the country. Since May, the percentage of Republicans who express satisfaction with the direction of the country has plunged 17 points. It’s clearly a reflection in part of Trump; when he was inaugurated, satisfaction among Republicans jumped by twice that much.

One of the key arguments that Trump made on the campaign trail last year was that most Americans thought the country was on the wrong track. Most Americans still feel that way, and the percentage who said they did climbed from March through the early part of this month.

Americans were growing more pessimistic — although that trend has reversed a bit of late.

That’s the whole thing with polling: They are snapshots of moments, not complete films. For Trump, though, an erosion in support is particularly bad news, because it’s safe to assume that members of his party who are up for reelection next year are paying close attention to how strongly Republican voters feel about him. If he becomes a severe liability for Republicans in Congress, the ramifications could be severe.

We’re not there yet. The question is whether Trump keep driving toward that cliff, Thelma-and-Louise style, or if he (or someone else) finally turns the wheel.