The Spanish government had a vested interest in exploiting the Americas for its resources, and it did not want anyone interfering with its plans. The Catholic Church also had a vested interest in the Americas, as it was responsible for converting the indigenous people to Christianity. Las Casas' criticism of the Spanish government and the Catholic Church's treatment of the indigenous people was seen as a threat to both institutions.
In addition, las Casas was also taking a personal risk by speaking out against the Spanish government and the Catholic Church. He was aware that he could be arrested, tortured, or even killed for his actions. However, he felt compelled to speak out against the injustices he had witnessed, and he was willing to risk his own life in order to do so.
Las Casas' support for the American Indians was a courageous act that helped to bring about change. His writings helped to raise awareness of the plight of the indigenous people, and they inspired others to stand up for their rights. Las Casas' work is still influential today, and it continues to inspire people to fight for social justice.