Is President Donald Trump responsible, in some sense, for the mailing of bombs to Hillary Clinton and other Democratic leaders? Is he responsible, in some sense, for the slaughter at the Pittsburgh synagogue?
If we are speaking in terms of causation, the most reasonable answer to both questions, and the safest, is: We don’t really know. More specifically, we don’t know whether these particular crimes would have occurred in the absence of Trump’s hateful and vicious rhetoric (including his enthusiasm for the despicable cry, “Lock her up!”).
But it’s also safe, and plenty reasonable, to insist that across the American population, hateful and vicious rhetoric from the president of the United States is bound to increase risks of violence. Because of that rhetoric, the likelihood of this kind of violence is greater than it would otherwise be. The president is responsible for elevating the risk that people will try to kill Democrats and others seen by some of his followers as “enemies of the people” (including journalists and Jews).
To see why, we should investigate one of the most striking findings in modern social psychology that has been replicated on dozens of occasions. It goes by the name of “group polarization.”
The basic idea is that when people are listening and talking to one another, they tend to end up in a more extreme position in the same direction of the views with which they began. Groups of like-minded people can become radicalized.
A little over a decade ago, I was involved in a study of group polarization in politics. We asked left-of-center groups to deliberate about three issues: same-sex unions, climate change and affirmative action. We asked right-of-center groups to do the same thing.
The results were straightforward. On all three issues, the left-wing groups ended up marching to the left, and the right-wing groups ended up marching to the right.
Trump is a one-man group polarization machine. At his speeches and online, he convenes like-minded people and gets them enraged. Those who criticize him are not critics; they are enemies.
If the president says that Hillary Clinton committed a crime, it is only natural for members of his audience, listening and talking with one another, to conclude that she should be locked up. And if “Lock her up!” becomes a standard cry, it is inevitable that some will progress to, “Kill her.”
Indeed they have, not only privately but also in public. For example, New Hampshire State Representative Al Baldasaro, a Trump supporter, said in a radio interview that “Clinton should be put in the firing line and shot for treason.” Roger Stone, a Trump adviser, tweeted, “Hillary must be brought to justice - arrested, tried and executed for murder.”
If people are talking that way, there is an elevated risk that sooner or later, someone is actually going to try to kill her - and others whom the president treats as enemies of the people.
The problem is compounded by the contrast between the president’s demeanor in two different situations: when he is speaking of national unity and when he is on the attack against his supposed enemies.
When he speaks of unity, he seems scripted and insincere. He reads from a text. He is working. When he is on the attack, he is in his element. He needs no text. He is having fun. Everyone can see that.
Responding to the possible connection between Trump’s despicable rhetoric and the recent crimes, some Republicans have been engaging in a form of “whataboutism,” pointing to what they see as abhorrent words and actions from Democrats. Let’s assume (in my view wrongly) that some Democrats have been equally willing to speak in an incendiary way.
So what? This is not some kind of competition. The question is not who started it or who’s worse. The question is whether the president of the United States has been elevating the risk of murder. The answer is clear: Absolutely.
Cass R. Sunstein is a Bloomberg Opinion columnist. He is the author of “The Cost-Benefit Revolution” and co-author of “Nudge: Improving Decisions About Health, Wealth and Happiness.”