President Barack Obama shakes hands with Richard Stone, chairman of the Conference of Presidents of Major American Jewish Organizations, after signing the United States-Israel Enhanced Security Cooperation Act. The measure won approval from Congress July 17. Under the bill, the U.S. will authorize $70 million in aid to Israel to expand its short-range rocket defense known as "Iron Dome." The bill's signing coincides with Republican presidential candidate Mitt Romney's visit in Israel this weekend.