Good Passports and Bad Passports
Imagine the aliens have landed. They have parked their spacecraft, or beamed down, and now here they are. And contrary to all the apprehensions the people of Earth have – thanks to every alien movie ever made – they are here to make friends, exchange ideas, maybe help us end poverty, war and disaster… But NOT SO FAST! Can we see your passports first? Don’t have passports, do you? And no visas either, then? Well, terribly sorry, this way please for immigration detention. And deportation as soon as we’ve built a rocket that can get you back to where you came from at the speed of light. Ta-tah!