By a remarkable coincidence just as I was reading your question I was watching the BBC Parliamentary Channel, and Llew Smith put almost the same question to Defence Secretary, Geoff Hoon. The Minister responded that the cases of Israel and Iraq were not comparable, because (a) Iraq's record in waging war and using weapons of mass destruction was unique, and (b) the UN Resolutions on Israel also referred to the obligations of other Middle East nations, which had also not been complied with.