Madison responded to Jefferson in October 1788. He denied that he had ever really opposed a bill of rights; he just didn’t think such “parchment barriers” were very important. He conceded rather halfheartedly that a bill of rights “might be of use, and if properly executed could not be of disservice.” Besides, “it is so anxiously desired by others.” But then he went on with one of his usual perceptive and probing analyses of politics in an effort to explain why he had originally been reluctant to back a bill of rights. Such bills of rights in the state constitutions had not been very effective in protecting the people’s liberties. In addition, writing out the rights might actually limit them. He was especially concerned with the rights of conscience, which “if submitted to public definition would be narrowed much more than they are likely ever to be by an assumed power.”

But then he proceeded to put the issue in its proper context and to explain to his friend that the classical theories of politics were no longer applicable in America. He told Jefferson that he appreciated the “tendency in all Governments to an augmentation of power at the expense of liberty.” The power of the one and the few had always posed a threat to the liberty of the many. But this was not the problem in republican America at that moment. “Wherever the real power in a Government lies,” he said, “there is the danger of oppression. In our Government the real power lies in the majority of the Community, and the invasion of private rights is chiefly to be apprehended, not from acts of Government contrary to the sense of its constituents, but from acts in which the Government is the mere instrument of the major number of the constituents.” There was no doubt, said Madison, that magisterial or executive “power, when it has attained a certain degree of energy and independence goes on generally to further degrees” and to become despotic and subvert liberty. Then a bill of rights protecting the people’s rights made sense. “But when below that degree,” which was the present situation in republican America with its weak state governors, “the direct tendency is to further degrees of relaxation, until the abuses of liberty begat a sudden transition to an undue degree of power.” Too much democracy—licentiousness, in other words—led not to anarchy, as the classical theorists had predicted, but to a new and unprecedented kind of popular power or tyranny. The United States, he said, had little to fear from the classic abuse of power by the few over the many. “It is much more to be dreaded that the few will be unnecessarily sacrificed to the many.”37

Wood, Gordon S.. Power and Liberty (pp. 97-98). Oxford University Press. Kindle Edition


Underlines are mine.  I highly recommend this short book on the background to the Constitution by one of the best scholars on the founding.  This may have been one of Madison’s most astute predictions, coming from his experience in the Virginia legislature under the Articles of Confederation.  There was more than just the lack of power that the central government needed to function properly that the current alliance circumvented.  There was also an abuse of democracy that mere modification of the Articles could not address.

In classical political theory excessive democracy descended into a mob that cycled into a tyrant.  Madison saw that majoritarian democracy could become tyrannical on its own.