Harvard University law professor Alan Dershowitz. Photo: Maxine Dovere.

Alan Dershowitz, who has made much of his friendship and fireside chats with former Harvard Law School colleague U.S. President Barack Obama, said he now doubts his friend’s promise to prevent Iran from gaining nuclear weapons.

Speaking on the sidelines of Israel’s Globes 2013 Israel Business Conference, Dershowitz said, “Obama promised me in a personal conversation that Iran would not develop a nuclear weapon on his watch, and I believed him. Nonetheless, I am not sure that he can keep this. Therefore, Israel cannot outsource its security.”

In an interview with Israeli television presenter Ya’akov Eilon, Dershowitz said, “There is the potential for disaster in the deal with Iran; too much was given for too little in return. The White House told me that this is not true. I was told that it will be possible to reapply the sanctions by the U.S. alone. I am afraid of the music not the lyrics. Iran hears this as the end of the sanctions regime in exchange for which they have to give up nothing. If this ends by stopping the nuclear development, I’ll applaud Obama.

“The President told me that there’s a 50/50 chance of success or failure. I think that the chances of success are only 20%, the chances of failure are 40%, and the rest is uncertain. I think that no one knows whether Iran’s supreme leader has changed his mind and that he is prepared to eliminate the nuclear program. We don’t know if he just put up a smiling face.

“Another point that really scares me is that the supreme leader called Iran’s Jews and told them to stand behind the nuclear facility and to say that they support the nuclear program. This is a message to the Israeli prime minister that they will use Iran’s Jews as a human shield. The message to Netanyahu is – don’t dare use the military option.”

Speaking directly about the Jewish state, Dershowitz said, “Israel is very strong in the face of external economic threats. Israel has created a wonderful army and has also succeeded in its business, in human capital, despite the regional threats. It won’t always be able to do this. The sanctions that parties want to impose have not succeeded.”

But he hard sharp criticism for how Israel portrays itself in the world: “Israel gets a C-grade for public relations in the world. It hasn’t done good work at all. Israel has no foreign policy, only a domestic policy. Everything here is political, so the attempt to defend Israel is always an attempt to defend the government, which is a huge mistake. Israel needs a lot of young people to defend it. The mistaken perception of Israel is of a country that is derelict in its conduct on human rights.”

Dershowitz, 75, became famous in 1967, when, at 28, he became the youngest full professor at Harvard Law School. As a criminal appellate lawyer, he has won 13 of the 15 murder and attempted murder cases he has taken on, and represented several high-profile clients, including Mike Tyson, Patty Hearst, and Jim Bakker.

Dershowitz’s most notable cases include his role in 1984 in overturning the conviction of Claus von Bülow for the attempted murder of his wife, Sunny, which was made into a book and a movie, and as the appellate adviser for the defense in the O.J. Simpson murder trial, in 1995.

His books include Reversal of Fortune: Inside the von Bülow Case (1985), the basis of the 1990 film; Chutzpah (1991); Reasonable Doubts: The Criminal Justice System and the O.J. Simpson Case (1996); the best-selling The Case for Israel (2003); Rights From Wrongs: A Secular Theory of the Origins of Rights (2004) and The Case for Peace (2005).