Just name recognition, that’s the main requirement for the majority of these institutions. Plus, throw in the liberal agenda and if you are a true believer and down for the cause, you can make a living at it. Hell, if you are Secretary of State, you and your husband can get filthy rich.
It takes more than that.
The speaker also has to be a Leftist, conservatives, or even middle of the road, are seldom speakers.
Condoleezza Rice had been invited to speak there last year, but there was so much pushback form Leftists that she declined.