How much influence does the U.S. have over Israel when it comes to Iran?
Not as much as some think:
“A strike at this time would be destabilizing and wouldn’t achieve their long-term objectives,” [Chairman of the Joint Chiefs of Staff General Martin] Dempsey said of the Israelis. “I wouldn’t suggest, sitting here today, that we’ve persuaded them that our view is the correct view and that they are acting in an ill-advised fashion.”
Dempsey doesn't think a strike would be prudent "at this time." But he didn't predict the future - or the present, for that matter, given his candid comment about the Israelis.