A group of Senate and House Democrats were blocked from entering the headquarters of the U.S. Agency for International Development (USAID) on Monday. The Democratic lawmakers, who are opposed to President Trump’s efforts to shut down the agency, left without incident after a brief exchange with security officials. The group, led by Sen. Chris Van Hollen (D-Md.), were told the front office of the administrator of USAID was not available to meet. A select group of USAID employees with the front office administrator were in the office Monday, an official told lawmakers outside the doors, but were not free to...