PALM BEACH, Fla. — Democrats just came up with a catchy-sounding bill to force President Donald Trump to cough up a list of visitors to his private clubs. But there’s just one problem: There are no lists yet. On Friday night, guests streamed into Mar-a-Lago, the president’s self-proclaimed “southern White House,” for the annual Palm Beach GOP Lincoln Day Dinner. All they had to do to get into the seaside retreat, where the first lady and the president’s youngest son were vacationing for spring break, was buy a $300 ticket. They didn’t have to submit to the kinds of rigorous...