Freed Israeli nuclear spy Mordechai Vanunu said in an interview published today that Israel was behind the 1963 assassination of U.S. President John F. Kennedy, prompting some Israeli officials to hope aloud the far-fetched comments will hurt Vanunu's credibility. Vanunu, a former nuclear technician who was recently released from Israeli prison after serving an 18-year sentence for exposing Israel's nuclear program at Dimona to Britain's Sunday Times, has been barred from leaving the country, talking to the media or meeting with foreigners. But the London-based al-Hayat newspaper published an interview yesterday it claims is the first Vanunu has given, in...