UFOs are government technology
A lot of people think that UFOs come from outer space and that aliens are visiting us.
People forget that in the 1940s the military were secretly working on the flapjack fighter.
When you look at these pictures you can see why people would get them confused with UFOs, flying disc and the sort.
I think there is a possibility the government could be peddling the alien story and letting people run with it / giving it ammunition to cover up this top secret tech and what's really going on.