This is a trend that has been building for some time but over the last two years acquired galvanic force. Why? Is it because the nature of the threat that Donald Trump represents to the left? Is it because, as Victor Davis Hanson has argued, Trump denied the left the power it considers its due? Or is it because Barack Obama, despite all of his purple rhetoric and fantastic publicity, was unable even to approach his goal of “fundamentally transforming” America—because he left the Democratic Party a smoking ruin, and bequeathed a regulatory and policy legacy as fragile as a paper crane?

All of these explanations for the resurgent left have some merit. I am especially partial, naturally, to the one that pins responsibility on Obama, who raised the hopes of a generation that the waters would cease to rise only to hand over command of the ship eight years later to Donald Trump and become a Netflix producer. Still, it is important to recognize that the collapse of the center-left is not limited to America. It is a global phenomenon. Obama and Clinton may have broken the Democratic Party, but don’t hold them responsible for the destruction of the French Socialists, the fall of the Italian Democratic Party, the takeover of Labor by Jeremy Corbyn, the worst result by the German Social Democratic Party since World War II, and the triumph of López-Obrador in Mexico.