The government wants you to believe.
Archived version: https://archive.is/newest/https://gizmodo.com/pentagon-has-been-pushing-americans-to-believe-in-ufos-for-decades-new-report-finds-2000614615
Disclaimer: The article linked is from a single source with a single perspective. Make sure to cross-check information against multiple sources to get a comprehensive view on the situation.
It’s not a matter of hearing of it before; it’s a matter of applying Occam’s Razor. How gullible does a person have to be to look at a super-secretive Air Force base that’s nevertheless known to be a testing ground for experimental aircraft, and then think the weird lights flying around above it must be aliens instead of just weird, fancy jets?