On 7 April 2018, in a nondescript conference room down in the bowels of Rome’s Church Village Hotel, Cardinal Raymond Burke was midway through a speech on the limits of papal power.

Speaking in Italian and reading from a pre-prepared text, the United States’ cardinal, a prominent critic of Pope Francis, started to explain the process of how to correct the Roman Pontiff. As he spoke to the crowd of several hundred, there was an outbreak of clapping and cheers before a small group suddenly shouted out: “People of God, stand up! We are the ones who have to act!”

It was a striking display of how visceral and vitriolic opposition to the 266th Successor of St Peter has become – and all of it at a location just two miles from the Vatican.