Every president of the last three decades has tried and failed to secure peace between Israel and the Palestinians. But most of the speakers and panelists seemed confident that Obama can fix this thing—if not once and for all, at least for a while.

Well most Presidents of the last three decades, even including Bush, managed to secure a peace that lasted "for a while". That can't possibly be the goal. So...this passage doesn't make any sense. Either he secures a little cease-fire, like his predecessors, and therefore isn't special; or, he secures a lasting peace, which everyone at this conference knows he's not going to.