At a speech in Davenport, Iowa, on October 24, with 13 days left in the presidential election, Barack Obama introduced a new closing argument: “Trust matters,” Obama said. “There’s no more serious issue on a presidential campaign than trust.” We agree. It’s a good way—among the most important ways—to evaluate a leader. On October 18, five weeks after terrorists attacked the U.S. consulate in Benghazi, Libya, killing four Americans, President Obama told television host Jon Stewart that his administration had moved quickly to share all of the intelligence with the public. “Everything we get, every piece of information we get—as...