At dawn in Switzerland, I read the alert: Charlie Kirk, 31, shot dead at a Utah Valley University event. This isn’t a verdict on his ideas; it’s a warning. A murder on a debate stage signals that words are losing to force. He built a career on argument; answering it with a bullet declares debate illegitimate. When speech is branded “violence,” real violence follows. Accept that trade and the liberal promise collapses into nihilism—and so, eventually, does civic peace.

The day was cold and grey. The clouds had arrived rapidly in droves across the valley. Winter is here; I sighed between my heavy breaths...