A new report by the Center for Strategic and International Studies (CSIS) claims Israel acting alone will not be sufficient to stop Iran's nuclear program. There will have to be U.S. strikes if it's to be successful.
According to the report, only the U.S. has the weapons capable of delivering the blows necessary to stop Iran's nuclear progress. The same report suggests that Israel, acting alone, only has the power to delay Iran's development for a year or two.
The report also says that because an Israeli attack would not completely incapacitate Iran, it might only lead to greater instability in the region and an Iranian response that would include Hezbollah fighters. Hezbollah leaders have long indicated they would attack Israel in the event of a strike on Iran.
Part of this report is congruent with concerns expressed by Israeli Defense Minister Ehud Barak, who believes Iran is moving to facilities as deep in the ground as they can. The further down they move, the harder it is for Israel to reach them. Consequently, Barak has made the point that if Israel doesn't act quickly, it will be up to the U.S. to stop Iran.