Amicable Aliens landed and were disgusted by what they saw.
And decided to take charge. Immediately.
Anyone committing a violent act had to learn 100 happy words and use them repeatedly. If they couldn’t do that they were sent to Rancor of Russia. And never heard from again. If they were already in the Rancor of Russia, rumor has it they went missing.
The cruelest acts were often unintended reiterations of past bad behavior. Hypnotherapy was used to free people from the clutches.
Anyone who swore had to do volunteer work such as picking up trash to help make the environment cleaner.
The streets of Manhattan had never been so clean. In Hollywood, you could eat off the freeways. Noise pollution helped fuel all kinds of other pollution and the world got cleaner.
The world still wasn’t perfectly kind, but this was a good start.