Tiannamen could have ballooned into a full on revolution, there were many killed, imprisoned indefinitely with arbitrary trials, hurt, families threatened, careers stomped out etc..
To add:
Kent State was a spontaneous situation, violence broke out at a student sit in, with thousands of students potentially overwhelming a small number of state troopers, some of whom foolishly shot into the crowd.
Kent state and Tiannamen are hardly comparable.
Tiannamen could have ballooned into a full on revolution, there were many killed, imprisoned indefinitely with arbitrary trials, hurt, families threatened, careers stomped out etc..
To add:
Kent State was a spontaneous situation, violence broke out at a student sit in, with thousands of students potentially overwhelming a small number of state troopers, some of whom foolishly shot into the crowd.
Fundamentally not comparable.