Adam Garfinkle has a very good piece in Tablet Magazine about the the changing dynamics among Washington, Jerusalem, and American Jewry. He attributes it to changing demographics among both American Jewry and Israeli Jews as well as to the increased power of Israel. From 1948 until 1977 the Israeli leadership and the leadership of American Jews both sprang from Eastern Europe: from the Jewish ghettoes in the major cities and the shetls of the former Austro-Hungarian and Russian Empires. American Jews could interpret Israel to Washington and Washington to Israel.
But this became less important over time as goyim, like myself, formed direct impressions of Israel through study abroad programs and more Israelis began to arrive in the United States as either diplomats, yordim (emigres), or military officers. In 1967 Israel demonstrated its value as a strategic asset by not just beating the Arabs as in 1948, or trouncing a single Arab state as in 1956, but in demolishing three Arab armies simultaneously. Then a decade later Oriental Jews began to move into power through the victory of the Likud. The Likud had different values from many American Jews: it was not social democratic, it was annexationist, and even more than Labor it was dependent on the support of religious Zionists and ultra-Orthodox who rejected the Jewish bona fides of much of the American Jewish community i.e. all non-Orthodox denominations.