President Trump’s decision on Monday to expel 60 Russian intelligence officers from the United States is welcome and apt. It is a proper response in support of an ally to Russia’s March 4 poisoning of a British intelligence agent, his daughter, and a police officer.

“With these steps,” the White House said, “the United States and our allies and partners make clear to Russia that its actions have consequences, the United States stands ready to cooperate to build a better relationship with Russia, but this can only happen with a change in the Russian government’s behavior.”