“I looked into it Reagan never held out the possibility of an invasion from outer space...”
Strange how you would say that, seeing he mentioned it in the speech. But I am not familiar with that speech, the one I had in mind was the one he gave in Iceland where he said he would continue to develop SDI and one of the reasons he mentioned was to repel an invasion from outer space. One of Gorbachev’s requirements for an agreement was for the U S to give up SDI. Reagan refused, the deal fell through.
Reagan didn’t say or think that an alien invasion was possible, he was using what used to be a common example of things that would expose the temporary nature of animosity between nations and people.
It used to be common for a lot of us to use that example and it was very common in Cold War movies, that the free world and the Soviets would unite to protect Earth from an outside force, such as comets or space invasion, which means we can unite without it, peace is possible if we just keep working at it.