Mead explains New England's - and America's - roots in moralizing governments. A quote:
New England government was charged with the creation of a moral society. There was nothing that was not its business: how much did a master pay his apprentices? Who celebrated Christmas? Who was cheating on his or her spouse? The duty of government was to make society live right; the university, the pulpit, the newspaper — these were to be the allies of government in the struggle for good.
Even after the old alliance between church and state in New England was broken up for good (the establishment of religion at the state level lasted almost 50 years after the ratification of the Constitution in Massachusetts and Connecticut) the acolytes of New England righteousness worked to make the American government a force for the moral uplift of the American people. Many of their causes today look prescient: the abolition of slavery and voting rights for women. Others, prohibition, eugenics and various forms of food-nuttery matching the changing scientific fashions of the day, look weird.
Over the centuries, New England has changed its theology while remaining loyal to its cultural foundations.