“How Would We Respond to an Alien Invasion?” from Strange Mysteries.goes like this, with some amount of prescience.
The video gives a dark future for us at first: conscription and the imposition of martial law, under world government. Everything might go on a wartime footing, like before WWII. The film even has a map showing which countries have conscription now. But the aliens might be here to do us good.
There is a bonus (paywall):
"“What Happens when we Find Alien Life?"
“Could Human Beings Be Living on Other Planets Right Now?” (link) looks at panspermia and examines the theories of Conway Morris, who predicts most intelligent beings capable of a modern civilization might look like us – maybe more limbs. Convergent evolution has produced the eye many times.