George Weigel is distinguished senior fellow of Washington’s Ethics and Public Policy Center, where he holds the William E. Simon Chair in Catholic Studies.

On January 22, 1899, Pope Leo XIII addressed an encyclical letter to Cardinal James Gibbons of Baltimore and, through him, to the entire Catholic hierarchy of the United States. Entitled Testem Benevolentiae (A Witness of Good Will), the letter raised cautions about attitudes and theories that some churchmen feared were corrupting the integrity of Catholic faith and weakening Catholic witness in the United States. The fretting churchmen in question were largely Europeans who bundled their concerns under the rubric “Americanism.”

Leo’s warnings came amidst a period of squabbling within the American hierarchy, and reactions to the papal letter fell along predictable party lines. Cardinal Gibbons and his party — which included the larger-than-life figure of John Ireland, archbishop of St. Paul, Minn. (and a former Union chaplain in the Civil War), and Bishop John J. Keane, first rector of the recently founded Catholic University of America — denied that any responsible churchman was teaching the dubious ideas of the “Americanism” against which Pope Leo warned. The opposition to Gibbons and his friends — led by Archbishop Michael Corrigan of New York and the ever-contentious Bishop Bernard McQuaid of Rochester — thanked the pope for saving the faith in America from a real and present danger. That bifurcated response to Testem Benevolentiae has been replicated in the subsequent writing of U.S. Catholic history, although the ideological positions of the debaters have reversed.

That Leo’s alleged “Americanism” was a “phantom heresy” — a reflection of squalid Church politics in Europe rather than an indictment of any views actually held by Catholics in the United States — was the line long maintained by classic historians of American Catholicism, including the modern dean of that guild, Father John Tracy Ellis (himself the principal biographer of Gibbons). Then came the Sixties and Seventies, and a revisionist school of U.S. Catholic historians began to argue that there were, in fact, adventurous currents at work in American Catholic intellectual and pastoral life in the late 19th century, advocating a rather different idea of the Church from that which prevailed in Roman circles at the time....