I would think if anyone does not know who Nasrallah, Zawahiri, and Baghdadi are, they are low information people. Julani, the leader of the al Nusra Front, can be forgiven if not recognized. If someone has read newspapers for the last 15 years and has some long term memory should know these names without a doubt. It would be like a candidate in 1968 saying they do not know which countries that Ho and Mao guys lead.
Just listened to the interview, and it is stunning that someone running for the presidency is this ignorant. Trump not only does not know who Nasrallah is, but does not know what Hezbollah is either. If a candidate professed this degree of ignorance 60 years ago, they would have been laughed out of the race. Today, it seems no big deal. As a people, we have sunk to a sad level. Right, Left, Center, our politicians display a level of ignorance and low brow rhetoric that would horrify the likes of Clay and Webster.