Let us never forget that government is ourselves and not an alien power over us. The ultimate rulers of our democracy are not a President and senators and congressmen and government officials, but the voters of this country.
Whatever is not commonly seen is condemned as alien.
There may be aliens in our Milky Way galaxy, and there are billions of other galaxies. The probability is almost certain that there is life somewhere in space.
I believe alien life is quite common in the universe, although intelligent life is less so. Some say it has yet to appear on planet Earth.
The more you can increase fear of drugs and crime, welfare mothers, immigrants and aliens, the more you control all the people.