Rich Lowry: Trump vs. the Khans

Donald Trump got sound advice the other day. At a rally at Davenport, Iowa, he told the crowd that a prominent supporter had called and urged him not to sweat all the attacks at the Democratic National Convention.

"Don't hit down," the supporter urged, according to Trump. "You have one person to beat. It's Hillary Rodham Clinton." By Trump's account, he conceded the good sense of this, although he noted how he always prefers hitting back – "it makes me feel good."

If so, he must have enjoyed his weekend. He spent it attacking not just Khizr Khan, the Muslim father of a soldier killed in Iraq w...