Bangladesh, July 4 -- The United States has reached a historic milestone. Two hundred and fifty years after the adoption of the Declaration of Independence, the country marked its semiquincentennial with grand celebrations, military displays, fireworks, and patriotic ceremonies designed to honor one of the worlds oldest constitutional democracies. Yet the defining image of this anniversary may not be the celebrations themselves, but President Donald Trumps speech beneath the towering granite faces of Mount Rushmore.

Standing before the monuments of George Washington, Thomas Jefferson, Abraham Lincoln, and Theodore Roosevelt, Trump declared America “the most successful, most accomplished, most exceptional nation ever to exist in hum...