The political upheavals in the Arab world-and, in particular, Egypt-have added to the sense of alarm among those Israelis who believe the country is facing a mounting existential threat. Although the 1979 peace treaty that Israel signed with Egypt has been in some respects a disappointment (see In focus), there is no doubting its importance in ensuring a lengthy period of peace between the two nations, as well as securing important co-operation on security matters-especially along Egypt's border with Gaza. If a democratically elected regime eventually assumes power in Egypt, we believe that it is unlikely to rescind the peace treaty, given the mutual benefits that it confers. But a much more worrying outcome for Israel (and the West) would be an Egyptian government dominated by the Muslim Brotherhood. Although the movement is making strong attempts to shed its pariah status, its refusal to acknowledge the legitimacy of the Israeli state-together with its support for the Hamas-led administration in Gaza-are perceived as serious threats by Israel.