When I was there in the 60’s the Puerto Ricans hated the Cubans. The very small group of independistas were the revolutionaries (much like today;s antifa) and they dynamited communication towers and causeed havoc every once in a while. They were small in numbers but a dangerous threat. They were heavily supported with arms and explosives from Cuba whose commandos brought boatloads of munitions into hidden beaches.
The Puerto Ricans I met in my work and in the community were pro-American, some veterans, and mighty good people.
I served with a lot of NYC Puerto Ricans in the Marines, early 70s...............