The often ruthless work of spy agencies like Israel's Mossad is justified when it saves hundreds or thousands of lives. That's the view of journalist Ronen Bergman, who's spent almost ten years researching and writing a book on Mossad. He tells us about the organisation's successes and failures, as he admits innocent people have died and that killing a man no longer requires even the prime minister's approval. It's a hard-hitting image of Mossad, but one he says is understandable for a country constantly battling terrorism. His book "Rise and Kill First" has just been published in French.