President Donald Trump promised he’d get rid of bad rules. “Remove the anchor dragging us down!” he said when campaigning for president. “We’re going to cancel every needless job-killing regulation!” Trump was a developer, so he knew that the thicket of rules government imposes often makes it impossible to get things done. But would he keep his deregulation promise? I was skeptical. Republicans often talk deregulation but then add rules. People called President George W. Bush an “anti-regulator.” But once he was president, he hired 90,000 new regulators! Trump has been different. When he took office, he hired regulation skeptics....