It’s been called the last refuge of scoundrels. It is undeniably linked to “us-against-them” tribal impulses, rooted in emotion and often impervious to reason. It feeds nationalism and militarism, making it a potentially dangerous phenomenon in a world of modern weaponry. Yet patriotism—outward, vocal, and enthusiastic patriotism—is still considered a vital element in American politics, an aspect of our culture that we …