By Henri Astier BBC News The power of America's "Jewish lobby" is said to be legendary. Commentators the world over refer to it, as though it were a well-established fact that US Jews wield far more influence than their numbers (2% of the population) would suggest. But this presumed influence is also a delicate issue in the US, and is rarely analysed. How does the lobby work? Is its power truly legendary, or just a legend? Two US academics, John Mearsheimer of the University of Chicago and Stephen Walt of Harvard, have set out to answer those questions, and triggered a firestorm of controversy as a result. Their book The Israel Lobby and US Foreign Policy, which builds on a 2006 article in the London Review of Books, says the reasons for US support for Israel need to be explained. [Many critics] tried to smear us by either saying or hinting that we are anti-Semitic Stephen Walt America spends $3bn a year in largely military assistance - one-sixth of its direct aid budget - to help a prosperous, nuclear-armed country, and strongly backs Israel in negotiations on Middle East peace. [color=3]But according to Mearsheimer and Walt, the US gets remarkably little in return. They reject the argument that Israel is a key ally in America's "war on terror". On the contrary, they contend, US patronage of Israel fuels militant anger - as well as fostering resentment in Arab countries that control vital oil supplies.[/color] One-sided The authors also reject the common view of Israel as a democratic outpost that needs protection from deadly enemies. It is indeed a vibrant democracy, they say, but also a regional giant ready to use its considerable firepower against civilians. If both these arguments are weak, they say, the real reason behind US support for Israel is domestic - the activities of the American Israel Political Action Committee (Aipac), the Anti-Defamation League (ADL), and like-minded groups and think tanks. Mearsheimer and Walt do not talk of a "Jewish lobby", as these groups do not speak for all US Jews and include many non-Jews, but of an "Israel lobby", whose main aim, they say, is to convince America that its interests are aligned with those of the Israeli state. The book analyses the lobby's sources of influence - notably its financial muscle and the reluctance of critics to speak out. Pro-Israeli contributions to US campaigns dwarf those of Arab-Americans or Muslim groups. Like other interest groups, the Israel lobby also influences debate by rounding on politicians and commentators who take positions it does not like - but it does it particularly effectively, according to Mearsheimer and Walt. Those who might think of questioning US support for Israel know they are in for a fight, making it more trouble than it is worth. The resulting lack of discussion, the book says, has skewed US policies across the Middle East. Most controversially, it argues that the lobby played an important role in the Iraq war. No conspiracy Perhaps not surprisingly, Mearsheimer and Walt have unleashed a torrent of criticism - though not from Aipac, which has made no comment. For any anecdote they come up with, you can come up with an anecdote that demonstrates the opposite "Their conclusions are classic anti-Semitic canards - such as control of foreign policy against the interest of the US, the Jews controlling the media and getting America into war," ADL director Abraham Foxman told the BBC News website. After reading the original article, Mr Foxman wrote a book-length rebuttal entitled The Deadliest Lies: The Israel Lobby and The Myth of Jewish Control.