Here are some quotes from an article contrasting the Catholic adoption of Aquinas with the Protestant adoption of Augustine.
Aquinas leads to attempts at a one world government:
Maritain has contended that world government “…perfectly squares with the basic principles of Thomas Aquinas’ political philosophy.”
~11. Jacques Maritain, Man and the State (Chicago: University of Chicago Press, 1951), p. 197. For the relevant works of Adler and Hutchins, see Mortimer Adler, How to Think About War and Peace (New York: Simon & Schuster, 1944); Robert M. Hutchins, St. Thomas and the World State (Milwaukee: Marquette University Press, 1949).
Reaching back through Aquinas to Aristotle, Maritain agreed with Hutchins and Adler that the pivotal point is Aristotle’s notion of the “perfect” state being based upon “self-sufficiency.” In Aristotle’s day that meant the city state, while in the modern era, argues Maritain, this means world government because with the interrelatedness of earthly life only a world state would meet the Aristotelian test of “self- sufficiency.”
~12. Maritain, Man and the State, p. 197. For a similar rationale also see, Hutchins, op. cit., passim.
“…the Catholic tradition…points clearly toward the necessity of world government….Catholics have, then, always been virtually for world government.’’
~15. Ibid., p. 39. [referring to 14. Hutchins, op. cit., pp. 41-42.]
“According to the mind of St. Thomas, only the world state can now be the perfect community.”
~16. lbid., p. 44. [referring to 14. Hutchins, op. cit., pp. 41-42.]
What will this entail for the West?
Maritain argued there is needed a “kind of moral heroism” on the part of “occidental nations,” for there will have to be “…a serious lowering of…standards of life, in order to provide people on the other side…with an equivalent raising of their standards of life.”
~13. Maritain, Man and the State, p. 208.
What is the antidote to utopian attempts at a one world government? Augustine!:
Whether reflected in the fanatical forms of fascism and communism or the more genteel forms of contemporary liberalism, St. Augustine is unsurpassed as an antidote to this powerful force. Throughout his extensive writings, which include some three hundred and fifty treatises, five hundred sermons, and two hundred extant letters, Augustine reflects the fundamental Judaic-Christian view which teaches us there are moral absolutes even though they may be dimly perceived by finite, fallible man. It instructs us that man is not the center and measure of all things, but rather God is. In contrast to his Creator, man is, in addition to being finite and fallible, characterized by a nature that has its “evil” side. Because of these limitations of man there will always be imperfections in the world regardless of the structure of human institutions. Out of this perspective springs the realization that men will never be as gods, and that some tragedy is inherent in the human condition. Armed with such realism, there is an acceptance of what Miguel de Unamuno called “the tragic sense of life.” Man cannot wholly eliminate the storms and vicissitudes of this earthly life as the utopians would do. At best he can alter a portion of them, through faith endure the balance, and by the act of endurance ultimately prevail. To the utopian mind this is all baffling and perhaps even humorous. But to those who accept this perspective, it is “realistic” and “relevant,” for it explains and accounts for more of the human condition than shallow secularism does.
Source and read more: http://www.theimaginativeconservative.org/2013/09/the-political-relevance-of-st-augustine.html