Answer:
He technically did regret the decision on sending the guards
Step-by-step explanation:
Nixon was could not sleep for 4 days straight because of this insident. But this was because of the Vietnam war and the, people that died we're in a sort of riot, because of the bombarding of Cambodia, because of the states military forces.
In a way the guards where triggered I guess since even the shooting and the death of 4 had a even more massive outrage on the other campuses, around the entire country.