Since the September 11 attack, US President George W. Bush has 【21】______ himself as a superpower leader of hard resolve, tolerating no 【22】______ to his goals-until he came up against Israel. 【23】______ the past week he has faced a dramatic 【24】______ to his international authority from the Jewish state. Israel is the chief US ally in the Middle East and 【25】______ of the largest chunk of US foreign aid. Stung by 【26】______ Israeli defiance, Bush on Monday urged Israeli Prime Minister Ariel Sharon publicly, 【27】______ the third time, to withdraw his forces 'without delay' 【28】______ Palestinian areas. A bloody offensive has been 【29】______ there for 11 days. He sent envoy Anthony Zinni to deliver the message personally as Secretary of State Colin Powell 【30】______ a new US initiative to 0chieve an Israeli-Palestinian cease-fire. Israel Radio reported later on Monday that the army began pulling out of two West Bank cities within hours. 【31】______ there was no 【32】______ that a full withdrawal might follow. Some analysts 【33】______ the standoff as an unprecedented and 【34】______ damaging 【35】______ between the United States and Israel, which annually receives US $3 billion in US aid. The US administration has sent enough 【36】______ messages to suggest Bush may not be 【37】______ rigid as his words appear. Until recently, Bush, conducting his war on terrorism around the world, had given. Sharon a 【38】______ free hand to go after Palestinian militants following a wave of suicide bombings that killed scores of Israelis. Powell's peace mission began in Morocco and will land him in Israel on Friday. Analysts say this will give Sharon time to finish his crackdown. Analysts said Bush could be sincere in wanting Israel to withdraw but was trying to have it both ways—continuing to give Israel some flexibility while 【39】______ US credibility with Arabs by talking tough to Sharon. Powell's mission got off to a frosty start on Monday, 【40】______ , when Morocco's King Mohammed asked him why be had not headed first to Jerusalem. 【21】