By JIM GERAGHTY, National Review Here’s an observation about the Republican presidential primary: Every now and then, I’ll hear someone express a preference for a candidate with the words, “I like what he’s saying.” I don’t want to disparage anyone’s criteria for picking a candidate, but I will note that saying things that you, the voter, like to hear is really just about the easiest part of running for president. You don’t have to actually do anything; you just toss out a bunch of ideas and repeat the ones that get the most applause. Anybody can show up and promise, “I’ll do this,” or “I’ll do that.” And the candidates who are really unprepared for the job think it will be easy. There’s only so much a president can do with executive orders, given that the next president of the opposite party can rescind such orders with the stroke of a pen. To really enact lasting changes, a president must be able to persuade Congress to turn his agenda into law. The job of the president is...