It’s the Age of Sanders, Too | The Vermont senator has pushed the Democratic Party toward radicalism, antisemitism and redistribution.

Graham Platner’s victory in Maine’s Democratic Senate primary was a personal triumph for the 41-year-old Marine veteran and campaign novice. His win also forces us to look at the last decade of U.S. history from a different perspective. Americans think of the years since 2015 as the Trump Era. Politics, entertainment, foreign policy, education and even sports have been defined in relation to President Trump and the MAGA movement. Tell me where you stand on Mr. Trump, and I’ll have a pretty good idea of your views on a variety of questions, from trans rights and tax cuts to national...