Americanism is the heresy that seeks to win over non-Catholics by watering down or ignoring sublime truths of the Catholic faith. This form of false evangelization was named by Pope Leo XIII in his 1899 apostolic letter Testem Benevolentiae Nostrae, addressed to the archbishop of Baltimore.
Leo XIII warned that true Catholic unity in worship, doctrine and government is not obtained by diluting or hiding Christ's teachings. He described this duplicity as follows:
[In] order to more easily attract those who differ from her, the Church should ... make some concessions ... not only in regard to ways of living, but even in regard to doctrines which belong to the Deposit of the Faith ... to omit certain points of her teaching which are of lesser importance, and to tone down the meaning which the Church has always attached to them.
The pope further noted Americanism emphasizes so-called "active" virtues of social welfare and democratic equality while devaluing the "passive" virtues of humility and obedience to Church authority. He clarified that Americanism had little to do with the U.S. legal structure or mindset of the nation's people: "Americanism ... if by this name are to be understood certain endowments of mind which belong to the American people ... and if, moreover, by it is designated your political condition and the laws and customs by which you are governed, there is no reason to take exception to the name."
The pope said his letter targeted a translation of the biography of U.S.-born Fr. Isaac Thomas Hecker, Servant of God and founder of the Paulist Fathers. The pope doubted the United States had this problem, saying that if it did, "there can be no manner of doubt that … the bishops of America, would be the first to repudiate and condemn it."
His letter, however, proved prophetic. Roughly 70 years later clergy began glossing over the Deposit of Faith to foster false unity and began exalting social justice while ignoring religious life.
Take a deeper look at Americanism in Church Militant's Premium show, Mic'd Up—Americanism.