Contrary to popular belief among some Catholic groups that there is something inherently wrong in the American system as designed by the Founding Fathers, there is every indication that Leo XIII and other popes saw something special about the United States — in a good way.
This is not idle speculation. Alexis de Tocqueville mentioned in Democracy in America that he considered American political institutions to be in conformity with Catholic teaching, and that the United States could one day be a “Catholic” country.
Cardinal Satolli’s enthusiastic characterization of the U.S. Constitution and the Gospels as “the Magna Charta of humanity,” and some of the language used by Pius XI in describing the act of social justice as well as his analysis of the role of free association have distinct parallels with the opinion and even language of de Tocqueville. As G. K. Chesterton remarked,
“It may have seemed something less than a compliment to compare the American Constitution to the Spanish Inquisition. But oddly enough, it does involve a truth; and still more oddly perhaps, it does involve a compliment. The American Constitution does resemble the Spanish Inquisition in this: that it is founded on a creed. America is the only nation in the world that is founded on a creed. That creed is set forth with dogmatic and even theological lucidity in the Declaration of Independence; perhaps the only piece of practical politics that is also theoretical politics and also great literature. It enunciates that all men are equal in their claim to justice, that governments exist to give them that justice, and that their authority is for that reason just. It certainly does condemn anarchism, and it does also by inference condemn atheism, since it clearly names the Creator as the ultimate authority from whom these equal rights are derived. Nobody expects a modern political system to proceed logically in the application of such dogmas, and in the matter of God and Government it is naturally God whose claim is taken more lightly. The point is that there is a creed, if not about divine, at least about human things.” (G. K. Chesterton, “What is America?” What I Saw in America (1922).)
The problem was that by the time Leo XIII wrote Rerum Novarum, fundamental changes had already been introduced into the American system. These undermined not only what was uniquely American about America, but also virtually everything that appeared to make the American spirit so compatible with Catholicism.