That a military display on Independence Day proved to be controversial should not be surprising, even if one discounts the partisan tone of much of the criticism. Americans tend not to favor displays of military power, except in the aftermath of successful wars: The Civil War, World War I, World War II, and the 1991 Gulf War were all followed by parades. Military displays nonetheless have the benefit of showing the American people what their investment in national defense has yielded. Contrary to President Donald Trump’s assertion that “our nation is stronger today than it ever was before,” the “Salute...