The long-time human rights advocate served as U.S. ambassador to the UN from 2013 to 2017
Samantha Power, the former U.S. Ambassador to the United Nations, as his choice to lead the U.S. Agency for International Development (USAID)
Biden will soon announce his pick
The exposure adds another worrisome consequence following Wednesday's attack on Congress
Adelson died Monday night from complications related to treatment for non-Hodgkins lymphoma
Austin took a board seat with a predecessor to the weapons maker after retiring from the Army in 2016