For the descendants of the defeated, there were commemorations, too. “There is no end to remembering,” German President Frank-Walter Steinmeier said at the Neue Wache memorial in Berlin. “There is no redemption from our history.”

The coronavirus pandemic has reminded us of how much World War II is hard-wired in the West’s political imagination. Tens of millions of people died in six years of conflict and genocide; that epochal horror and sacrifice still serve as a kind of inescapable benchmark for much of the world.

U.N. Secretary General António Guterres said the virus represents “the most challenging crisis we have faced since the Second World War” — which led to the creation of the institution that he now leads. Last week, Trump described the disease’s “attack” on the United States as “worse than Pearl Harbor,” the 1941 Japanese air raid in Hawaii that brought the United States into the war. And Johnson, ever-eager to invoke the spirit of wartime hero Winston Churchill, sought to summon his legacy to the present fight. “On this anniversary, we are engaged in a new struggle against the coronavirus which demands the same spirit of national endeavor that you exemplified 75 years ago,” he said in an address hailing the surviving veterans of the war.

For weeks, historians have reached back to the experience of World War II in search of useful lessons for this moment. In Europe, the trauma of the war now forever lurks beneath the continent’s appeals for unity and solidarity. In the United States, the great wartime mobilization of resources and manpower seemed to reflect what this unique nation was capable of achieving when set against a global, existential threat.

Of course, there’s a limit to these metaphors’ potency. In geopolitical terms, the Trump administration and nationalist governments elsewhere in the West are almost explicitly interested in breaking up the post-World War II political and economic order, not rallying it. Euroskepticism is as virulent in some countries, and possibly even more so in others, than it was before the virus arrived. And for large parts of the world — especially in South Asia and Africa — World War II is not the same bridge between two eras that it is for the West. Rather, it’s just a precursor to the greater unraveling of Europe’s empires, a story also steeped in blood and untold atrocity.

Some experts look optimistically for signs that the pandemic could engender a great renewal. “We might forgive our leaders’ frequent and self-serving language of war and their invocation of Churchill in 1940 if only it is accompanied by some of that wartime spirit that reset and expanded the boundaries of the possible,” wrote Oxford University historian Margaret MacMillan. “What had seemed fantastical or too expensive in peace — mass producing penicillin, splitting the atom, making jet engines — swiftly became reality. And, yes, such innovation can also happen in peace.”

“Many of the actions undertaken to put the United States on a war footing in the 1940s were natural outgrowths of Franklin Roosevelt’s decade-long attempt to equip the federal government with new capabilities and grant it the necessary authorities to overcome the Great Depression,” wrote Charles Edel, a senior fellow at the United States Studies Center at the University of Sydney. “The creation of new agencies and organizations was second nature to that generation, as was a willingness to experiment boldly, persistently, and swiftly on what might provide immediate relief for millions of affected Americans. Those habits have long since been forgotten.”

And maybe, as a virus paralyzes the globe, the lesson that matters is not one of leadership or courage or sacrifice, but something more tectonic and imperceptible. “From the vantage point of the 21st century, if there is a historical grand narrative that does justice to the significance of the 1945 moment, it is not that of international organizations like the Bretton Woods institutions or national welfare states,” wrote Adam Tooze, a historian and director of the European Institute at Columbia University.

It is, rather, “what 21st-century environmental historians call the ‘Great Acceleration,’ the vast and dramatic acceleration of humanity’s appropriation of nature that reached a turning point in the middle of the 20th century,” Tooze wrote. “In its globe-spanning dimensions, in its multifaceted integration of the land, the sea, and the air, and in its violent intensity, World War II was an anticipation and driver of that process, which continues down to the present day.”