Senator Chuck Schumer was skewered on social media and by late-night TV hosts last month after telling CNN’s Dana Bash that Democrats had fired off their written concerns to Trump about his targeting of Harvard university and other schools. The formal congressional letter has long been a way to demand information from Cabinet officials and to presage investigations. But at a time of growing Democratic frustration about what they see as insufficient pushback from their elected officials, the missives are drawing mockery. WASHINGTON ? As President Trump’s administration rolls out dramatic changes to the federal government and policy, lawmakers have...