President Trump’s campaign rallies are meant to center on one thing and one thing only: Trump. He holds the rallies, years before he’s on the ballot again, because it gives him two things that he greatly enjoys, a microphone and an adoring audience.

The coverage of those rallies and their popularity with his base, though, means that non-Trump issues seep into the public consciousness. Slogans, random individuals, people promoting causes. Trump is the main attraction, but sideshows can draw the spotlight.

One did on Tuesday. A number of people at Trump’s rally in Florida held signs or wore shirts referring to “QAnon,” a hopelessly complex and obviously unhinged conspiracy theory that centers on the idea of an insider in the Trump administration, “Q,” leaking information about the president’s secret work on uprooting child sex rings and building a case against prominent Democrats and celebrities for complicity.

These are the more normal and comprehensible components of the theory.

But why this? Why now? Why is this something that has managed to take root among supporters of Trump?

Decline in trust in the media

The likely path America took to get to this point starts with the decline in trust in mass media. This decline, well established in the public imagination, has happened more recently than many believe. As recently as 2005, half the country had a “great deal” or “fair amount” of trust and confidence in the media, according to Gallup polling. In 2016, driven lower by the presidential election, that figure was 32 percent. Last year, a slight rebound, driven by Democrats, to 41 percent.

Among Republicans, trust in the media stayed at a low of 14 percent.

The growth of the Internet, fostering other media and communities

That recent downward slide overlaps with the rise of the Internet and social media. The splintering of the media as an institution into a thousand outlets of varying intent and legitimacy has both blurred the line of what constitutes media (does Infowars count?) and painted media outlets generally with the broad brush of inaccuracy. Social media also allow examples of mistakes or bad arguments to spread rapidly, where they can be seized upon by those looking to disparage an outlet’s reporting as an example of why the outlet shouldn’t be trusted.

The Internet has also flattened time in a way that a mistake made years ago is as accessible and looks just as recent as one made yesterday. Those looking to build portfolios of skepticism against media outlets have a great deal of ammunition with which to do so. This is a recently popular rhetorical tactic: If there’s one counterexample to an argument, that argument is presented as obviously inaccurate. Scale vanishes; as long as any doubt can be introduced, reasonable doubt is granted.

In addition to the Internet providing a petri dish for media outlets of varying quality, it has served as fertile ground for communities more broadly. Before the Internet, people who enjoyed dressing as animals mostly led isolated existences; post-Internet, there are conventions for “furries.” If you like something, no matter how obscure, there thousands of other people who probably share that interest and with whom you can commune, both in real life and online.

That also means, of course, that there are self-selected communities in which various beliefs are similarly encouraged and reinforced. The Internet takes those string-and-photo walls of conspiracy theories and crowdsources them, bringing together largely self-policed groups of people to pick out whatever pieces fit whichever puzzles they want to solve.

The Internet also provides those pieces, offering a flood of information that can be used — directly or through questionable interpretation — to fit the pattern that those groups are seeking. There are few outside authorities who can or will weigh in with a dose of skepticism or reality, no Walter Cronkites or school principals who can step in and reel back the imaginations of the participants. There are just other like-minded people who already see reality through the same lens.

QAnon is a specifically Internet-based theory. It is discussed and furthered and bolstered by people in online discussion boards, seizing upon whatever evidence is at hand: random comments from President Trump, typos in his tweets, anecdotes dropped by Q.

Conspiracies get political — and aggressive

There was an inevitable overlap with politics, even assuming that the decline in media trust didn’t stem from partisan motivations. Many, skeptical about the mainstream media, have turned to sites like Breitbart, the conspiracy site Gateway Pundit or the aforementioned Infowars for news. Breitbart was the most-linked site on the right during the 2016 campaign, with Gateway Pundit in the top five on social media platforms.

Shortly before the election, there was an important but underrecognized movement that built a new set of tools for fighting online. “Gamergate,” as it was known, began as a putative attempt to address media coverage of video games but quickly spiraled into a web of conspiracy theories, social-media attacks and reinforcement of some sort of aggrieved status among young men. It established, among other things, a blueprint for bad-faith manipulation of the Internet against perceived enemies. Many of the subsequent campaigns targeting (often liberal or anti-Trump) public figures have employed tactics honed during Gamergate.

Fake news becomes lucrative

At the same time, Facebook had moved to the center of the media ecosystem, driving life-sustaining traffic to publishers struggling to navigate as businesses. In broad terms, though, the system rewarded information that would generate traffic and engagement, meaning that, among other things, it rewarded misinformation that bolstered partisan political beliefs.

That’s one undercurrent that barely needs to be mentioned: The sharp rise in partisanship and the slow increase in negative partisanship, seeing the opposing party as a risk or threat to the country.

There’s some psychology at play here. Rumors and untrue salacious stories are more interesting and get more attention on social media than the truth. It’s the truth-getting-its-boots-on aphorism operating at the speed of light. At the same time, people are often unwilling to challenge their existing beliefs and willing to subscribe to theories that conform with what they already think is the case.

Facebook became a place that people could make a quick buck making up news stories — and the stories that were most effective at generating engagement were often ones that bolstered conservative politics and Trump himself. Teenagers in a Macedonian village made a small fortune telling lies about the election, thanks to Facebook.

The social media site came into the campaign at a disadvantage in the fight against fake news. In May 2016, Gizmodo reported that the site’s trending topics bar was filtering out conservative outlets. Observers noted that the human moderators were largely doing what they were supposed to, filtering out untrue claims that happened to originate on these conservative sites. But it probably made Facebook wary about cracking down on questionable reports favorable to Trump more broadly.

The trends combine in 2016, aided by Trump

The 2016 election was a moment of sharp partisanship in which fighting dirty was seen as fair game. The tactics of Gamergate were deployed regularly against the media and against other opponents of Trump on behalf of the “alt-right,” a far-right movement that seeks a whites-only state, and whose supporters often shared Gamergate’s demographics, grudges and familiarity with the Internet.

Trump’s rise to the top of the field in the Republican primaries, meanwhile, was in part a function of his willingness to embrace the ideas and priorities that were reflected in conservative media, particularly Fox News. A steady diet of anti-immigration and anti-elite rhetoric came to the fore in Trump’s speeches and interviews in a way that most Republicans would have avoided. Whether his claims were true (often they weren’t), they were often what his base wanted to hear.

Building on his long-standing claims that President Barack Obama wasn’t born in the United States, Trump actively encouraged conspiracy theories about criminal aliens, about voter fraud that aimed to prevent his victory, about the purported criminality of his opponent. It was a dark, murky world that Trump saw around him, and he pledged to be the person to clear it all up.

At all levels, Trump found support for this line of thinking. Media outlets pored over emails stolen from the Democratic National Committee and Hillary Clinton’s campaign, picking out embarrassing or questionable items that often served to bolster Trump’s anti-establishment and anti-Clinton arguments. Others, reading more into those documents than was warranted, built out elaborate theories regarding satanic cannibalism rituals and, ultimately, a ring of pedophiles in Washington operating out of a small pizza shop in the District and that ensnared prominent Democrats.

This was Pizzagate, often cited as the go-to example of how conspiracy theorizing can spread online into weird places. Some of the online promotion of the theory was ironic or trolling, an effort to cause headaches for Trump’s political opponents or simply to stir things up. Much of it, though, was sincere.

Pizzagate then also became the go-to example of how such conspiracies can jump into the real world. In December, an armed man visited that pizza shop to rescue the children that his online community insisted were there. They weren’t, of course, prompting the man to lament that the “intelligence on this wasn’t 100 percent.”

In his community of Pizzagate theorists, there was no doubt that seeped in.

Trump continues to embrace conspiracies after the election

Once Trump was elected, his conspiracy theories changed in nature. No longer were the elites trying to throw the election against him, now they were trying to undercut his legitimacy by investigating possible ties between his campaign and the Russian effort to interfere in the election (manifested in part, allegedly, by stealing those emails from the Clintons campaign and the DNC).

It set up a weird dynamic. Normally, it’s those who lack power who create theories to undercut their opponents or strengthen their position. That’s not what Trump does.

“Powerful people can’t use conspiracy theories very well. They’re tools of the weak to attack the powerful,” University of Miami political science professor Joseph Uscinski said when I spoke with him last fall. “But what we’ve seen in this instance is because Trump has built his entire machine on conspiracy theories, that’s why we have dueling conspiracy theories. That’s why we have a narrative on the right and a narrative on the left.”

Trump allows conspiracy theories to exist because they serve his needs. At one point, the White House even granted press credentials to Gateway Pundit. As readily as he enjoys basking in the applause of his base, the president similarly seeks to shut out contrary opinions. He has built and now leverages a mostly sealed-off community in which he is a remarkable success and in which his critics are biased, conspiring against him or treasonous. Or all of these things.

It’s an effective tactic. As we reported last week, three-quarters of Republicans believe Trump more than the media. He has carved out a big part of America that assesses truth through the lens that he himself provides.

Trump supporters seize on alternative explanations

Within that region, as at his rallies, there are ancillary theories and voices that take root. Among them is QAnon.

QAnon posits, among other things, that Trump is engaged in a fight to uproot child trafficking internationally and that all of his weird or unexplainable actions are intended to that end. Why this obsession with pedophilia that manifests in QAnon and in Pizzagate? BuzzFeed’s Charlie Warzel, who has been tracking these trends for months, offers a rationale:

“The fever swamps have seized on this particular issue because they see it as an important moral high ground from which to wage an online culture war. Crusading against something as monstrous as pedophilia allows the pro-Trump media to see itself as a hero and makes their motives unassailable — they can call anyone who opposes their work as “pro-pedo.” And picking such a taboo area of advocacy allows some cover, as well. Given that actual child sex trafficking is a depraved, illegal world that operates out of plain sight, the pro-Trump media can point to its targets and suggest that it’s happening in dark corners without needing definitive proof.”

That last point is important. One role that QAnon plays is to establish an unprovable and un-dis-provable theory to explain any and all Trump actions and to explain away critiques. If the allegation is that his opponents are complicit in the darkest, most nefarious actions, that both establishes their own moral voice and the reason that those opponents’ misdeeds are so hard to see. Trump is battling an matter of life-or-death, tackling hidden forces in a largely out-of-sight war.

It is a near-perfect distillation of how Trump sees himself: America’s savior against powerful opposing forces. Trump explains away his errors and mistruths as bias or the actions of the “deep state.” QAnon’s efforts differ only in degree and contours.

What Trump doesn’t do is also important. He is always loath to criticize those who stand with him, allegedly asking then-FBI Director James B. Comey to give longtime adviser Michael Flynn a break, or declining to speak forcefully against far-right protesters in Charlottesville or, we can add, refusing to undercut Russian President Vladimir Putin in public. Trump could help stamp out QAnon and other conspiracy theories, but he chooses not to because they often serve his political ends.

None of this is entirely unique to Trump. There’s an ecosystem on the left that seizes on new rumors of collusion between Trump and the Russians and spins out densely strung webs of theories about how Trump was handed his position. But the situation with the president leverages a base that’s more skeptical of the media and more willing to accept his version of things and involves a president who’s willing to at least accommodate, if not encourage, far-fetched conspiracies.

QAnon is remarkable and alarming. But it isn’t surprising. Nor should it be surprising that it burst into the limelight, thanks to a Trump 2020 campaign rally held in July 2018.