Now at Harvard, the Obama administration alum admits it’s been hard to watch the Trump administration take aim at the work she’s proudest of. But she hasn’t lost hope. GINA MCCARTHY STRIDES INTO the ocean-view ballroom at the Sea Crest Beach Hotel in Falmouth, plops down her green backpack, and glances out the window. The waves are angrily advancing on this last night in April, which feels as dreary as mid-January. “The water seems way closer than it was the last time I was here,” she says. Maybe that’s because of climate change, the threat that McCarthy led the charge...