Front-page coverage and heated morning radio discussions asked how Professor Chomsky, an 81-year-old professor emeritus at the Massachusetts Institute of Technology, could pose a risk to Israel and how a country that frequently asserts its status as a robust democracy could keep out people whose views it found offensive.

Professor Chomsky, who is Jewish and spent time living on a kibbutz in Israel in the 1950s, is an outspoken critic both of American and Israeli policy. He has objected to Israel’s foundation as a Jewish state, but he has supported a two-state solution and has not condemned Israel’s existence in the terms of the country’s sharpest critics.

The decision Sunday to bar him from entering the West Bank to speak at Birzeit, a Palestinian university, “is a foolish act in a frequent series of recent follies,” remarked Boaz Okun, the legal commentator of the newspaper Yediot Aharonot, in his Monday column. “Put together, they may mark the end of Israel as a law-abiding and freedom-loving state, or at least place a large question mark over this notion.”