Finkelstein is not "controversial". He is the most benign researcher and has always said that Israel should exist as the Jewish State, opposed BDS and overall always had Chomskyite views, until very recently. He refuses to call Zionism colonialism. There is nothing controversial in his views, nothing even radical. Unlike Thomas Suarez or Miko Peled, he has never called for the dismantlement of Zionism and has never condemned Zionism as an ideology. Until recently, when he started to say things that suggest that he might have realized that this is not a project of national liberation, after all.
He is one of those liberals who continue talking about "Hamas behind October 7" although Hamas is a political party, the uprising was done by SIX Palestinian armed brigades, only ONE of them Al Qassam, the armed brigade of Hamas which does not even act according to some supervising orders, it is independent and has its own plans.
Hamas is not a military entity!