Uncovering and explaining how our digital world is changing — and changing us. The number of active hate groups in the United States has fallen by about 10 percent in the past year. This isn’t necessarily good news. There were 838 active hate groups this year, compared to 940 in 2019, according to an annual report by the Southern Poverty Law Center (SPLC). The organization attributes the drop to the fact that these groups have become more diffuse and difficult to track, largely because of changes in technology. The pandemic has also played a role in limiting in-person activities. Even then, 838 is still a very high number of active hate groups. In 2000, there were 599 hate groups on the list. It peaked in 2018 with 1,020 groups, which reflects a surge in extremism that has paralleled Donald Trump’s rise to national office. Even if the overall number is lower this year, the SPLC warns in its latest report of a “reactionary, authoritarian populism that is mobilizing on the heels of Trump’s loss.”