This shooting is all of the above, and none of the above, and something else entirely: a powerful reminder of just how polarized the country is on issues like abortion, gun control, and terrorism. “People will apply the arguments that are most familiar to them,” says Brendan Nyhan, an assistant professor of government at Dartmouth College who studies confirmation bias. “We’re going to get this odd mixture of different responses and competing interpretations—is this a mass shooting event, is this an anti-abortion event, is this a domestic terrorism event?”