This is an explanation from Walter Russell Mead of why Benjamin Netanyahu received such a warm reception. I think it’s a little heavy on the religion side, but I think it’s essentially correct (emphasis mine):
As the stunning and overwhelming response to Prime Minister Netanyahu in Congress showed, Israel matters in American politics like almost no other country on earth. Well beyond the American Jewish and the Protestant fundamentalist communities, the people and the story of Israel stir some of the deepest and most mysterious reaches of the American soul. The idea of Jewish and Israeli exceptionalism is profoundly tied to the idea of American exceptionalism. The belief that God favors and protects Israel is connected to the idea that God favors and protects America.
It means more. The existence of Israel means that the God of the Bible is still watching out for the well-being of the human race. For many American Christians who are nothing like fundamentalists, the restoration of the Jews to the Holy Land and their creation of a successful, democratic state after two thousand years of oppression and exile is a clear sign that the religion of the Bible can be trusted.
Being pro-Israel matters in American mass politics because the public mind believes at a deep level that to be pro-Israel is to be pro-America and pro-faith. Substantial numbers of voters believe that politicians who don’t ‘get’ Israel also don’t ‘get’ America and don’t ‘get’ God. Obama’s political isolation on this issue, and the haste with which liberal Democrats like Nancy Pelosi left the embattled President to take the heat alone, testify to the pervasive sense in American politics that Israel is an American value.
Read the whole thing.