about justice for the poor and oppressed.

They also attacked the hypocrisy of the religious right who put rigid moralism before compassion. Let's not forget what our strength is for, they cried: not to lord it over the other nations but to serve a vision of global harmony. They came out with heart-stopping rhetoric about God's justice filling the earth like the waters fill the sea, and all tears being wiped away.

In America this prophetic tradition was fairly well integrated into mainstream politics, for centuries. Then a new, intense variant of it emerged: Martin Luther King, and the civil rights movement generally. Here was a vivid replaying of the Exodus story. America had thought itself the chosen people, and then a new Moses type came along and everything was turned upside down. The idea of America as a new version of Israel collapsed, with the warriors going one way and the prophets of peace the other.

Obama could not be more firmly in the prophetic tradition. His first memoir is essentially a story of being called to

a special role of quasi-religious leadership. There are even echoes of the Moses story in his gradual, angst-ridden discovery that his true identity lay with the oppressed. His calm rhetorical power is a sign that he wears the mantle of Martin Luther King.

But he has the sense to widen the appeal, to make his open-air church tones appealing to whites, and those wary of gloopy liberal sentiment. For he understands the divided state of American religion, and knows he must appeal beyond the prophetic heartland. He even signals his respect for the warrior tradition, which insists that national security comes first.

At the penultimate debate he promised to do his utmost to find and kill Osama bin Laden, and the violence felt odd, like Jesus advocating stoning. But this is what he has to do, if the balance of this God-rocked nation is to be restored.