By Simon Lewis, Nidal al-Mughrabi and Emily Rose AMMAN/CAIRO/JERUSALEM (Reuters) -The top U.S. diplomat swept through the Middle East on Sunday, warning that the Gaza conflict could spread across the region without concerted peace efforts, although Israel’s leader vowed to continue the war until Hamas was eliminated. U.S. Secretary of State Antony Blinken, at the start of a five-day trip in the region, also sought to assure Arab leaders that Washington opposes the forcible displacement of Palestinians from Gaza or the occupied West Bank. “This is a moment of profound tension for the region. Th…