Complex sentence: As the Cathedral of the Pope'qua' Bishop of Rome, it ranks superior to all other churches of the Roman Catholic Church, including St. Peter's Basilica, and therefore it alone is titled "Archbasilica" among all other basilicas.
Split into simpler sentences: As the Cathedral of the Pope qua Bishop of Rome, it ranks superior to all other churches of the Roman Catholic Church, including St. Peter's Basilica. For that reason, it alone is titled "Archbasilica" among all other basilicas.