"NO MUSIC!" screeched a little green alien. He fired his freeze-ray at a pedestrian whistling "when Johnny comes marching home again", who wobbled, then fell over. A team of slightly less little aliens picked him up and lifted him onto one of their hovercarts. "This one will be placed in isolation! You all must learn your place!"
A crowd of people turned away. But I just had to look. One of the grunt aliens started humming, and the lead alien freeze-rayed him as well.
Straightening my tie, I walked into the United Nations, now renamed Colony Liaison Building, and prepared for negotiations. My human colleagues were all gathered, but the aliens seemed to be running late.
I mused to Rosanna, sitting next to me. "This ban on music ..."
"Yet another psychological snub," she groused. "Music unites humanity so they want to stamp it out. It's like disallowing conquered people from speaking their native tongue. I wouldn't be surprised if that comes next."
"It may be more than that," said I. "I suspect they find music ... contagious." I arched my eyebrows, imparting a secret. "I saw them take down a whistling pedestrian this morning. They were almost panicking. And one of the alien guards started humming, and they took him down too."
Rosanna sat back. Surprised. Entertained. "I noticed their commander, Major Tom, humming yesterday at the end of the meeting. Pachabel's Canon, I think."
Eventually the aliens came in. A new, grumpy alien was leading the procession. "What happened to Major Tom?" I asked.
"He ... was called away on important business," said the new alien. "Earth is not our only concern. From our perspective, it's just a small world."
"Yes," I said. I spoke in a storytelling voice. "It's a world of laughter, a world of tears. It's a world of hopes and a world of fears."
Nodding in agreement, Rosanna picked up the ball, continuing the story. "There's so much that we share that it's time we're aware it's a small world after all."
And the whole human contingent burst into song.
This was in response to a prompt on reddit.com r/WritingPrompts, "An enemy subjugates humanity and they seek to stop music in all forms as it unites humans. Humanity has other plans."