VATICAN DIPLOMAT WHO TOOK ON THE POPE

The letter, published Sunday, has challenged Francis’ papacy and shaken the Roman Catholic Church to its core. The pope has said he won’t dignify it with a response, yet the allegations have touched off an ideological civil war, with the usually shadowy Vatican backstabbing giving way to open combat.

The letter exposed deep ideological clashes, with conservatives taking up arms against Francis’ inclusive vision of a church that is less focused on divisive issues like abortion and homosexuality. But Viganò — who himself has been accused of hindering a sexual misconduct investigation in Minnesota — also seems to be settling old scores.

As the papal ambassador, or nuncio, in the United States, Viganò sided with conservative culture warriors and used his role in naming new bishops to put staunch conservatives in San Francisco, Denver and Baltimore. But he found himself iced out after the election of Pope Francis.