2016 was “a banner year for hate,” according to a new report by the Southern Poverty Law Center (SPLC).

SPLC cited some of the typical reasons for that label: Donald Trump, whose campaign relied largely on anti-immigrant and anti-Muslim rhetoric and anti-black dog whistling, won the 2016 election. There was an increase in reports of hate acts following his win. And the deadliest mass shooting in US history was an explicitly anti-LGBTQ attack at a gay nightclub.

But SPLC also cited a new finding in its report: 2016 saw an increase in the number of known hate groups, driven in large part by a 197 percent increase — from 34 in 2015 to 101 last year — in anti-Muslim hate groups. In total, there were 917 hate groups, up from 892 in 2015 but below numbers seen earlier in Barack Obama’s presidency.

“Hate groups remain at very high levels and in fact went up last year for the second year in a row,” Mark Potok, a senior fellow at SPLC, told me. And, he added, the increase in anti-Muslim hate groups was historic — far above what SPLC found in previous years.

It would be one thing if this were just one report. But there are other statistics that show anti-Muslim sentiment in particular is leading more and more Americans to act in more hateful ways.

The surge in anti-Muslim hate has been building for years

Potok pointed out that SPLC’s latest report is not the only one to find an increase in anti-Muslim hate. Late in 2016, the FBI also put out a report that found a 67 percent increase in reported hate crimes against Muslims from 2014 to 2015. While the FBI’s overall count of hate crimes is generally considered a huge underestimate of the total hate crimes in the US, the spike in anti-Muslim hate crimes was big enough, Potok said, to potentially suggest a real shift since at least 2015.

“It’s true that the total numbers are misleading,” he told me. But “while it may not be true that [anti-Muslim] hate crimes went up exactly 67 percent, I don’t think there’s any question that we saw a dramatic surge in anti-Muslim hate crimes in 2015.”

One reason for the increase in anti-Muslim hate, according to Potok, is President Donald Trump’s campaign: “We think that is driven very largely by the really terrible demonizing statements that have come out of Donald Trump and out of the Trump campaign about Muslims in this country — the idea that they should be banned from this country, that we should start a registry to keep track of Muslims in this country even if they’re American citizens, that we should be spying on mosques, and so on and so on.”

It’s also likely that Trump was riding on an anti-Muslim wave that has been prevalent in America for years, fueled by fears of Muslim extremists who carry out terrorist attacks around the globe. A recent survey from the Pew Research Center, for example, found that out of the major religions, US adults tend to hold the most negative views toward Muslims.

One potential glimmer of hope: The Pew survey also found that Americans reported warmer feelings toward Muslims in 2017 compared with 2014. So while some Americans may be acting on their hate by increasingly joining hateful groups, the broader trend seems to be moving in a more welcoming direction.

Other hate groups didn’t see big increases, but there’s still cause for concern

There was some good news in SPLC’s report: There wasn’t a notable increase in other kinds of hate groups. That allowed the overall count to remain below 2008 through 2011 levels, when sentiment against President Obama, Potok said, fueled a surge in hate groups’ recruitment.

But he cautioned, “I think this understates how much hate there is out there.”

For one, it’s possible that SPLC just couldn’t identify some of the smaller hate groups. Although SPLC tries to thoroughly comb through websites, citizen reports, police reports, field sources, and news reports for its data, it’s always possible that some groups slipped through.

Potok also pointed to the number of “lone wolves” that carry out hateful acts or hold hateful beliefs without joining a hate group. Consider Dylann Roof, a self-described white supremacist who shot and killed nine people at a black church in Charleston, South Carolina. Roof wasn’t part of a formal hate group and never appeared to have been in contact with hate groups, so someone like him wouldn’t appear on SPLC’s map. But he clearly believes in many of the same ideas that empower hate groups.

SPLC found a small uptick in the number of black separatist groups, which espouse anti-white and anti-Semitic views in defense of black supremacy. “These groups are profiting, essentially, from all the attention paid, especially since the events in Ferguson, Missouri, to police killings of black men,” Potok said. “That whole issue of police brutality directed at black men has helped very legitimate civil rights groups like Black Lives Matter grow. But at the same time, black extremist groups … have also grown.”

Still, the increase in these and other groups not focused on Muslims was fairly minor. The real story, based on the SPLC report, was the rise in anti-Muslim hate — a trend that has reared its head time and time again in America over the past few years.

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