BRASILIA( Reuters)-A bill allowing commercial agriculture and mining on protected tribal reservations in Brazil advanced in Congress on Tuesday in what indigenous leaders said could be the biggest setback since their land rights were guaranteed in the 1988 Constitution. The proposal, known as PL 490, cleared the constitutional affairs committee and headed for the lower house plenary.... Brazil's powerful farm lobby and far-right President Jair Bolsonaro have pushed for the bill, arguing that in