You realize that the vast majority of the men responsible for bringing the United States into existence were actually more "traditional" in terms of their values and morality than their European counter-parts of the same era, correct? Franklin, for example, was rather impressed with the degree of wanton debauchery tolerated in London or Paris that would have been utterly taboo back in the colonies.
In any case, you're confusing your terms. Political and economic "Liberalism" is not the same thing as being morally "liberal." They are fundamentally different things.