The way that the Alcatraz Proclamation and occupation showed the failures of the U.S. government was by exposing that the government was not abiding by certain treaties.
Native American activists occupied the closed Alcatraz in 1969 in order to protest against the U.S. government not abiding by land treaties they signed with the Natives.
This showed that the U.S. government was failing to protect all of its citizens which was a huge blow at a time when the world was against the racial policies of the U.S.
Find out more on the occupation of Alcatraz at https://brainly.com/question/470855.