I believe that General Powell identified himself as a republican in order to secure his rise within the system. He has always been a social liberal, believing in affirmative action and abortion. He is nothing but a RINO.
No one familiar with Powell's liberal political views can be the slightest bit surprised at his endorsement of a liberal candidate.
Profound ignorance of Powell's public record is a logical explaination for the bewildered consternation on display.