Why is the United States so moralistic, invoking God at every turn of the political roundabout? And why are its people so famously indifferent to international affairs? A nation which squabbles so much about government spending at home allows billions of tax dollars to be spent on foreign policy, yet takes little interest in where it is spent.
This is God's country, "the great idealistic force of history," as Woodrow Wilson saw it. For Ronald Reagan, it was an "anointed land set apart in an uncommon way". Madeleine Al bright's view is that: "We are the indispensable nation. . . we stand tall."
It is hard to credit that anyone takes this seriously. Yet there is reason to suspect that most US citizens - rich and poor - suspend their critical faculties at key junctures of national significance and ritually extol their nation as God's emissary on earth.
The contrast with Europe is striking. National pride is never absent from European hustings but the habit of attributing its source to the deity has long vanished. The French have a distaste for the intrusion of moralising into their actions and pronouncements on foreign policy.
British, German and Scandinavian modes of self-aggrandisement are also checked by the facts of history and show some restraint in recruiting God's purpose to human achievements.
Europeans have good reason to be self-critical. The US is not exempt from the corruption of power, but reality blurs when the nation compares itself with the rest of the world. Yet no western society has developed such a deep rooted suspicion of government. American moralism and insularity from world affairs both owe their origins to the theological contradiction in Calvinism on which the Founding Fathers drew to shape the republican experiment in the late 18th century. They learned that the righteous are the elect of God, the new Israel, set apart from the rest of humanity like a city on the hill.
But it was not this upbeat Calvin who spoke loudest to the early republic. Calvinism also taught a deeply pessimistic view of the frailty and sinfulness of all human endeavour, especially in earthly politics, and this strand impressed Franklin, Jefferson, Washington and their fellows.
For the first half century, any American temptation to vainglory was overwhelmed by pious apprehension about the frailty of government, their rulers' sinfulness and by a holy fear that their republic might fail as others had.
As power corrupted Rome so, it was thought, power would corrupt the new world. Thomas Jefferson articulated that fear in a memorable phrase which today would cause stupefaction or riot on Capitol Hill: "I tremble for my country when I reflect that God is just".
Time healed the trembling as the new republic survived and prospered, and its political theologians looked for new inspiration to the sanctimonious line of the Calvinist tradition. Thomas Paine's dictum, "We have it within our power to begin the world over again", took on a new meaning for later Americans, impatient with history and chafing at the bit of Calvinist self-doubt.
How did the US manage to incorporate the notion that it was "the new Israel", the "indispensable nation" into a political culture steeped in paranoid suspicion of government?
The answer is simple. Self-criticism is reserved for domestic politics and moralism for the rest of the world. The mistrust of government which afflicts attitudes to the exercise of power at home is never allowed to infect the standing of the American government in the international arena.
This is facilitated by the unique separation of powers which gives the president almost total authority in the conduct of foreign policy and reserves for congressional and public scrutiny the domestic policies and arrangements which directly impinge on the everyday lives of the people.
Moralism abroad fosters insularity at home. Who needs to read about the complexities of the world when they believe their nation is in charge because of God's mandate?
Ever since Washington and Jefferson, Americans have a holy fear of cohabiting with other nations in "permanent" or "entangling" alliances. Isolationism was originally a prudent injunction in the light of the unsavoury alliances available at the time. Today it is just a pious code of the conservative right for the doctrine of unilateralism - global intervention without the restraints of international institutions.
Early indications from the new administration suggest that unilateralism is the new agenda. God will not be slow to endorse it.
Dr Bill McSweeney lectures in international politics at the Irish School of Ecumenics, Trinity College Dublin. He is author of Security, Identity, and Interests: A Sociology of International Relations (Cambridge University Press)