Readers will know I’m no fan of Donald Trump. If he wasn’t prepared to defeat Iran and force regime change, he probably shouldn’t have attacked in the first place. But, having attacked, he is turning away from all-out war — on the grounds, he says, that he doesn’t want to be Herbert Hoover and start a world depression with high oil prices. He could equally have said Lyndon Johnson, who got the U.S. into the land war in Asia that Dwight Eisenhower, supreme commander of D-Day, always warned against. Trump clearly, and to his credit, is very reluctant to do that.