How many times do you tell someone not to touch a hot stove before you stand aside and let them do what they want?

This is the question experts — and Congress — now face when arguing with people who seem bent on hurting themselves by supporting President Trump’s policies, and especially his trade policies. It’s possible that the president is right, and that what America needs is a vicious trade war with its closest allies. History and experience, to say nothing of common sense, suggest that he is wrong.

More to the point, the people most likely to be hurt by this kind of recklessness are the very people who voted for Trump. And sure enough, some of Trump’s voters — such as farmers, or the small businesses that want special exemptions — are already squawking. And for once, some members of Congress have discovered their spines, because this issue is so deeply entwined with their own interests.