How Joe Biden’s surprisingly ambitious climate plan came together

During a recent virtual fundraiser focused on climate action, former vice president Joe Biden made a direct appeal to voters young enough to be his grandchildren.

“I want young climate activists, young people everywhere, to know: I see you. I hear you. I understand the urgency, and together we can get this done,” said the 77-year-old Democrat, who days earlier had announced a $2 trillion plan to combat climate change and environmental racism — the most ambitious blueprint released by a major party nominee for president.

The moment marked a...