With Covid cases surging in parts of the United States and vaccinations proceeding at a crawl, all eyes are on social media platforms. Many people, particularly some Democrats in Washington, appear to believe that online misinformation is at the heart of the flagging vaccination campaign. President Joe Biden summed up the mood when he suggested that Facebook was “killing people,” kicking off weeks of frenzied coverage. (He later clarified that he was referring to the purveyors of misinformation, not Facebook itself.) Then, late last week, Senator Amy Klobuchar of Minnesota introduced a bill that would strip away Section 230 immunity for vaccine content promoted by social media algorithms.

The Klobuchar bill is an apt mascot for the confused state of discourse over misinformation. Because it would direct the government to decide what counts as misinformation and then treat content differently on that basis, it would probably violate the First Amendment. Of course, Klobuchar’s proposal will never become law; it is what’s known as a messaging bill. And the message seems to be that, in order to close the vaccination gap and finally bring the pandemic to a close, social media platforms just need to do something.

That focus, though, may misdiagnose the problem. At least in the US, vaccine hesitancy appears to be a largely top-down partisan phenomenon, in which public behavior is influenced by elite messaging. As of last month, just over 10 percent of adult Democrats had not been vaccinated, compared to nearly 50 percent of Republicans, according to multiple surveys. (And while access is still an issue for some Americans, the most-cited reasons for not getting the shot come down to willingness, not ability.) As my former colleague Daniel Engber recently pointed out in The Atlantic, this partisan gap has been remarkably stable, and it precedes Fox News’ recent turn toward constant vaccine-skeptical coverage. The underlying cause for the partisan split, Engber suggests, might therefore be the fact that Republicans have, throughout the pandemic, been much less afraid of Covid than Democrats. The country’s most influential Republican, Donald Trump, relentlessly played down the risk of the disease from the start (including during his own hospitalization), and millions followed his cue. Research has found that the biggest predictor of whether Americans view Covid-19 as a threat is not their scientific literacy or demographics, but whether they trust Fox News and Breitbart over CNN and The New York Times. Viral rumors on social platforms may have widened the divide, but it seems clear that Republican Party messaging, amplified by its traditional media architecture, created it.

It’s also a mistake to assume that all anti-vaccine sentiment is based on misinformation per se. There has lately emerged a wealth of polling and news reports providing insight into the motivations of the vaccine-hesitant. One of the most common reasons they give for their reluctance is that we don’t yet know if the vaccines have long-term side effects. Another is that the Food and Drug Administration hasn’t officially approved any of the vaccines. Both of these facts are technically true. Are they sensible reasons to refuse the vaccine, in light of all we do know? No. But they are not false.

So it goes with a great deal of anti-vaccine messaging. Yes, many people who say they’re afraid of side effects have bought into false rumors about vaccines harming fertility or altering one’s DNA. But many are responding to real, if rare, reports of serious side effects; the government really did pause administration of the Johnson & Johnson vaccine because of a rare blood-clot disorder. Drug companies really are greedy. The right fact, presented without adequate context, can be more than enough to scare people away.

The most visible vaccine-skeptical public figures, the likes of Tucker Carlson or Senator Ron Johnson (R-Wisconsin), understand this. They don’t need to spread demonstrable falsehoods. They can simply focus night after night on outlier cases of severe side effects. Or they can selectively present results of scientific studies or government communications in ways that seem to suggest something ominous about either the virus or the vaccine. Or they can skirt the scientific question entirely in favor of ranting about how the government’s vaccine push is really about social control. Like any illusionist, they know that the most powerful tool available is not misinformation, but misdirection.