Those other nationas are the suppliers, moneybags, aiders and abettors of the bus-bombers. Time to strike them--hard.
It's imperative that Israel not let the "moral high ground" you speak seve as a graveyard. You don't lose your moral high ground by killing your mortal enemies. You affirm it.
Earlier this summer, Hamas leader Abdel Aziz Rantisi declared, "By G-d, we will not leave one Jew in Palestine (meaning Israel as well as the territories)," justifying his pledge by claiming, "This is our land, not the Jews'." Last year, the leader of Hizbollah, Hassan Nassrallah, mused, "If they (Jews) all gather in Israel, it will save us the trouble of going after them worldwide." And Hizbollah's protector, the Syrian government, is no less open about its desire to kill all Jews. Syria's Minister of Defense, Mustapha Tlass, opined in a television interview two years ago that if "every Arab killed a Jew, no Jews would remain," and added that he personally wanted "to kill any Jew he faced."
http://www.jewishworldreview.com/0803/mowbray_2003_08_28.php3
The appropriate response of Israel is to kill their enemy before the enemy gathers the strength to match his murderous intentions. It's called "self-defence."