Turning Turk in Othello

I found this article interesting and beneficial.  Vitkus explains what "the Turk" may have meant back then, beyond that what may have been meant by the phrase "turning Turk."  He explains that "turning Turk" may have been:

-a way for Christian captives to gain freedom from oppression

-a synonym for becoming a whore

-a name which referred specifically to the people from Morocco or Turkey

The author did his research, going so far as to looking into what the word "turn" may have meant, and compares it to other passages that include it.  They all had negative connotations, which I found interesting. 

I looked up what kind of connotation the term "Turk" has now, and nothing seemed negative. Results included "a member of the Turkish people" and "of Turkish language"- very different than the strong images Vitkus portrays.

Final thought:  Vitkus writes that a lot of comedies  included plots involving a male tricked into marrying an "honest whore."  What does that mean? He compares Desdemona - the "honest whore," with Othello-- "the noble Moor."  I can see how Othello is a noble Moor, but Desdemona did nothing wrong, so why is she a whore?