“If it were up to me, I would put in jail every sandal-wearing, scruffy-beard weirdo who burns the American flag.” I don’t know if you could quite fit that into a rally chant, but it is a memorable bit of reactionary sentiment from Justice Antonin Scalia. Shortly before he died, the great jurist was explaining why he voted against the criminalization of flag-burning (in the Supreme Court’s controversial 1989 ruling in Texas v. Johnson). With characteristic pith, he was illustrating something that ought to be patent: We often express passionately our most visceral feelings; but we do not act on these outbursts in actually lived life.

When we get down to brass tacks, principles, laws, and norms are honored. We have those guardrails precisely because we’re human, prone to error and excess, prone to let our id out for a night at the rally hall. We cannot help what we think in a gut sense, and liberty means being free to voice those thoughts, even when good judgment would counsel against it. But when we get back to reality, common sense and law take over.

We might say “Kill the umpire,” but we don’t actually want the umpire killed. We shouldn’t need to explain that because everyone understands it. The exercise of our right to scream “Kill the umpire” does not create a clear and present danger to umpires. For 60 years I’ve heard crowds say nutty things at carnival-type venues; on the other hand, I’ve also prosecuted people for inciting terrorist attacks against the United States. There is a palpable difference between provocative expression and incitement to violence, one that is not hard for sensible people to discern, even if great legal minds have struggled to articulate it precisely.