Senator J. D. Vance (R-OH), the recently announced Republican vice presidential candidate, instantly responded to the assassination attempt on Donald Trump by blaming the White House — tweeting that the attempt was not just an “isolated incident” but a reflection of the Joe Biden campaign’s core themes about Trump’s threat to democracy. (In fact, the attempted assassin, Thomas Matthew Crooks, was likely not motivated by progressive outrage against Trump, and early indications are that he was a Republican gun enthusiast.)

In effect, conservatives like Vance are appropriating the idea, long put forward by some liberals, that overheated political rhetoric is itself a form of violence. The theory of “stochastic terrorism” holds that over-the-top rhetoric about a targeted individual or group has the effect of encouraging “lone-wolf” political violence — that is to say, political violence carried out by individuals on their own initiative rather than terrorist organizations — and that this makes the purveyors of the rhetoric responsible for the violence.

I’ve never seen anyone consistently apply this theory. Invariably, overheated rhetoric that one finds unfair or irresponsible is blamed for violence against the targets of that rhetoric. Equally white-hot rhetoric that one agrees with, or that is put forward by factions to which one is basically sympathetic, is given a more nuanced treatment, and (appropriate) skepticism is applied to the chain of causation.

If you’re an antiabortionist who calls abortion murder, you might still think this doesn’t justify the murderers of abortion doctors taking the law into their own hands. If you’re a left-liberal who believes Trump is literally a fascist, you might point out that it hardly follows from this that shooting him would diminish the fascist threat. In all cases, I’d argue that the “stochastic terrorism” theory dangerously undermines free-speech norms by blurring the line between speech and violence. Let’s not go down that road.