Has John McCain grown up? Given the things the Arizona senator has done in his life, that might not seem a question that needs to be taken seriously. But it should be taken seriously because it could be a real factor in his campaign to win the Republican nomination for president.After McCain’s speech at Liberty University on Saturday, I posted an excerpt on National Review Online’s blog, The Corner. It was a passage in which McCain described how he had been a know-it-all in his youth and how the passage of time had made him more circumspect and less assured...