In his first public event since contracting COVID-19, President Trump told several hundred mostly minority and vocal supporters at the White House that Blacks and Hispanics are rejecting the Democratic Party’s turn toward socialism and embracing his law-and-order message. “Black and Latino Americans are rejecting the radical socialist left, and they are embracing our pro-jobs, pro-worker, pro-police … and pro-American agenda,” Mr. Trump said in an 18-minute address from a White House balcony overlooking the crowd on the South Lawn. The president said the members of Blexit, a group headed by conservative Black activist Candace Owens, understand that “to protect...