US casino billionaire Sheldon Adelson, a strong Israel supporter and backer of Prime Minister Benjamin Netanyahu, offered in 2013 to pay $1 billion for Iron Dome anti-missile batteries for Israel, Politico reported on Thursday.In a profile Politico wrote on US President Barack Obama’s chief-of-staff Denis McDonough, Nevada Sen.Harry Reid, then the senate majority leader, called Obama shortly after Congress passed a funding bill for the Iron Dome and relayed Adelson’s offer – “so committed was he to safeguarding the Jewish state “ – to finance the batteries.“Obama was thrown off his guard momentarily,” the story reported. “‘What?!’ he asked Reid. When the president regained his footing, he told the leader to thank Adelson, but that he didn’t think private financing of munitions would set a good precedent.”Adelson, who publishes the pro-Netanyahu Israel Hayom daily, reportedly spent $100 million in the 2012 US presidential campaign in a failed attempt to defeat Obama.He is also a huge contributor to Israel and Jewish causes. According to an article last month in The Jewish Journal, Adelson is slated to announce the establishment of a foundation that will allocate $200m. annually – half to Israel and Jewish causes, and the other half to medical charities.