The questions that haunted the Pontifical Academy for Life conference were familiar, controversial and exhausting, since Catholics and their bishops had been arguing about them for years.

The year was 2006, but little has changed in 2021.

What should bishops do when prominent Catholics -- even presidential candidates -- defended and promoted abortion rights? What if they said they accepted churched teachings on the sanctity of human life, while their actions suggested otherwise?

Would it violate the "separation of church and state" if bishops denied them access to Holy Communion? What if bishops asked these politicos to go to Confession?

"This is silly," said scholar Robert P. George, addressing that Vatican gathering. A Catholic shepherd "acting on his authority as a bishop to discipline members of his flock, who commit what the Church teaches are grave injustices against innocent human beings" would be "exercising his own constitutional right to the free exercise of religion. …

"Freedom is a two-way street. No one is compelled by law to accept ecclesiastical authority," stressed George, an outspoken Catholic layman and professor of jurisprudence at Princeton University. Thus, a bishop has "every right to exercise spiritual authority over anyone who chooses to accept it. There is a name for people who do accept the authority of Catholic bishops. They are called 'Catholics.' "

At that time, most debates centered on Sen. John Kerry, the Democratic Party's presidential nominee in 2004.

Cracks inside the U.S. Conference of Catholic Bishops widened with the election of President Joe Biden, a rosary-carrying Catholic who -- in word and deed -- has evolved into a fierce defender of abortion and LGBTQ rights. Biden quickly dropped his longstanding opposition to the federal funding of abortion, after criticism from the left in the 2019 primaries.

Despite fierce opposition from several U.S. cardinals, 75% of the U.S. bishops recently voted to proceed with a document on "Eucharistic coherence" in an age in which many Catholics reject key church teachings -- including the core belief that bread and wine used in Communion become the body and blood of Jesus.