Burke observes the "spirit of liberty" which is alive and well in the colonies, along with the obvious fact that their achievements outstrip those of the "Old World."
Frothingham's "Rise of the Republic of the United States" also couches the events of 1776 and 1787 in the rich ideas of liberty which existed and were being practiced among the colonists prior to the Declaration of Independence and Constitution.
Both of these works provide background for the work described in this article, for all who wish to pursue them.
Thanks for the information. Appreciated.