If Americans were unaware of the enormity of the Great War’s impact on Europe, they might have gained some insights watching the events marking the 100th anniversary of the end of World War I, the “war to end all wars” that instead paved the way for a second horrific world war. The ceremonies and the magnificent public art displays help us grasp the mind-boggling loss of men, the physical damage to Europe and the profound impact World War I had on everything from women’s rights to faith in technology as a force for human progress.

The commemorations also underscored the magnificent achievement of the post-World War II international liberal order — which prevented any wars of this magnitude, ushered in decades of prosperity and drew bitter enemies in to close alliances. One truly has to have a heart of stone and a lack of any understanding of the 20th century not to be moved by the sight of leaders of the European nations walking together in the rain down the Champs-Elysees or the obvious personal affection between German Chancellor Angela Merkel and French President Emmanuel Macron.

Macron’s speech was a perfectly delivered argument for preserving the international order and rejecting President Trump’s noxious nationalism. Macron explained, “Patriotism is the exact opposite of nationalism. Nationalism is a betrayal of patriotism. By putting our own interests first, with no regard for others, we erase the very thing that a nation holds dearest, and the thing that keeps it alive: its moral values.” He continued, “Old demons are rising again. New ideologies are manipulating religions, and history is threatening to repeat its tragedies. Let us vow once more as nations to ensure peace is the utmost priority, above all else, because we know what it cost.”

The solemnity and introspection of the world leaders stood in contrast to Trump’s nonattendance at a joint visit on Saturday to a cemetery (begging off because his helicopter was grounded due to weather, although other leaders managed to get there). More important, the tone of the proceedings contrasted with Trump’s juvenile attitude toward the military. Like a young child, he loves the pomp, and like a tin pot dictator, he likes to order about the military as if they were his own personal guards — though he has yet to visit them in a combat zone. (Is this his physical cowardice or his fear of comparison between his record — he escaped Vietnam due to “bone spurs” — and our brave, selfless men and women overseas?) Trump alone, physically and metaphorically, was the perfect reminder of the scourge of isolationism, xenophobia and nationalism.

Trump never seemed so small or as inadequate for the job as he did this weekend — when once more, in place of a representative of America’s moral core, there was a void. Without empathy or curiosity or historical knowledge or grace, Trump flops on such occasions, reminding progressives of the need for U.S. leadership in the world and reminding conservatives that for all their criticism of President Barack Obama, he conducted himself with great dignity at these occasions.

One can only imagine what the right would have done (call for impeachment?) had Obama begged off a cemetery visit or snubbed allies or sulked like a spoiled child. Today’s Republicans rationalize (because they are cowardly or intellectually corrupt) their support for a president who in every way is inferior to his predecessors and who acts with disdain for the principles they supposedly held. The challenge for the country and our allies is to hold it — the Western democratic experiment — together until a U.S. president worthy of the office in the mold of Franklin D. Roosevelt, Harry S. Truman, Dwight D. Eisenhower, John F. Kennedy or really any other modern president can replace Trump.

The West is fortunate to have Macron, Merkel and other responsible leaders — as well as the strength of the U.S. military — to keep the peace for now. But without a competent president who understands that America is the indispensable power — because it acts or aspires to act on universal values — free people remain at risk.

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