Former secretary of state John F. Kerry has lobbied to build support for the agreement on Iran, provoking President Trump.  (Alex Brandon/AP)

On Tuesday afternoon, President Trump made an announcement that has been expected since he won the 2016 presidential election: The United States will withdraw from the multinational agreement reached with Iran during the administration of President Barack Obama to curtail that nation’s nuclear program. Trump telegraphed this move repeatedly, including by bashing former secretary of state John F. Kerry’s efforts to build support to maintain the agreement.

Kerry and Trump are at the poles of opinion on the subject. Most Americans are presumably somewhere in the middle, though it’s not clear where. There has been a lot of polling that tries to get at that question, especially as a May 12 deadline to renew America’s participation in the deal approached. CBS and CNN, both working with the polling firm SRSS, and Pew Research Center have conducted surveys in the past two weeks to assess public opinion on the subject.

So how do Americans feel? Uh, well, it’s sort of hard to say.

Let’s start with that CNN poll. The results here seem to be pretty straightforward. About 3 in 10 Americans support withdrawing from the deal, and more than 60 percent want to keep it in effect. Among Republicans, the issue is remarkably split, with only an 8-point advantage to “withdraw.” Among those who approve of Trump’s job performance, responses were basically even.

So that’s one survey. But the one from Pew comes to a slightly different conclusion. It asked the question differently: Did respondents approve or disapprove of the deal?

A plurality disapproved, with Republicans (joined by Republican-leaning independents) disapproving much more than Democrats (and Democrat-leaning independents) supported it.

Those two surveys aren’t mutually exclusive. You could, for example, disapprove of the agreement but still think it was important to remain a participant. There’s a level of nuance to such a view that’s impressive, understanding both the flaws of the deal but also the benefits of maintaining it.

Is that what’s happening then? Do Americans have a nuanced view of the deal?

We turn to the CBS poll. Here, the question is phrased more like the one from CNN: Basically, what should the United States do? Among those who had an opinion, though, results were split. Half wanted to remain in the agreement; half wanted to leave it.

But that’s only among those with an opinion. CBS, unlike the other pollsters, specifically offered people an “I don’t know enough to say” option, as spotted by HuffPost’s Ariel Edwards-Levy. And, hey, guess what! That’s the option that most Americans chose, given the chance.

(The 50-50 split among those who had an opinion is visible in the chart at left. About a fifth wanted to remain in and a fifth wanted to leave, 50-50. Most, though, said they didn’t know enough.)

The picture that emerges then is slightly less generous than the one speculating that Americans had a nuanced view of the agreement. Instead, it seems that most Americans (including a majority of independents and Democrats) withhold an opinion on the subject when not forced to give one. When forced to give one — by polls that ask for a choice between two options — they tend to err on the side of skepticism about both the agreement and withdrawing from the agreement.

Nothing about this speaks badly of Americans. Most people certainly don’t know enough about the agreement to have a robustly considered opinion. It’s complicated, and the repercussions are uncertain even when considered by those who spend their lives looking at such things. It’s not unusual for Americans to raise an eyebrow at things they aren’t intimately familiar with — and the idea of making major, hard-to-assess changes to foreign policy. So we get a variety of polls that, more than anything, reflect uncertainty.

We’ll note, too, that the polls don’t seem to suggest that Trump’s decision will be a big political winner. The odds seem good that the effects of withdrawal will be subtle over the short term. His base will support fulfilling a campaign promise, but his base wasn’t going anywhere. Others might be increasingly frustrated at Trump’s willingness to tear up what former presidents had done, but his opponents have largely been unmoving, too.

The real question is if those short- and medium-term effects will be subtle. If they’re not, there could certainly be political ramifications — or other geopolitical ramifications that might make immediate domestic politics a secondary concern.