The US Institute for Peace (USIP) conducted on 5 June 2019 a two hour podcast with four former US ambassadors to Ethiopia. The session was moderated by USIP's Aly Verjee and Johnnie Carson, USIP's senior adviser for Africa, gave introductory remarks.
The four ambassadors were:
Marc Bass, 1991-1994
David Shinn, 1996-1999
Aurelia Brazeal, 2002-2005
Donald Booth, 2010-2013
Fred Strasser summarized their remarks in a 13 June piece titled "In Ethiopia, Former U.S. Diplomats See Promise in Reform."