A top American cardinal celebrated a traditional Latin Mass on Saturday in St. Peter's Basilica with the explicit permission of Pope Leo XIV, thrilling traditionalist Catholics who had felt abandoned after Pope Francis greatly restricted the ancient liturgy. Cardinal Raymond Burke, the conservative American figurehead, presided over the 2 1/2-hour liturgy, which was rich in hymn, incense and priests bowing to the altar, their backs to the faithful in the pews. For many traditionalists, the moment was a tangible sign that Leo might be more sympathetic to their plight, after they felt rejected by Francis and his 2021 crackdown on the old liturgy.