Do you think that the President of Columbia University is not seen as an American?
Another thing about "speaking truth to power" is that it is done from the people and for the people. An Iranian pointing out injustice to his president in the face of great danger is speaking truth to power. An American, making criticisms from a position of safety, with the power to issue invitations to presidents of nations, is in no position to play prophet.
Lilithu, I can understand that you look at the phrase "speak truth to power" in light of its religious/theological roots, but I was using the phrase in a much more casual and plain spoken manner and I have no theology about it.