True enough. The government probably lacks the capability of keeping aliens a secret, but it isn't above culpability. Just because a government may "fail to keep a secret," doesn't mean they don't exhaust resources in a feckless attempt to keep said secret. That's what my mother's issue was, the "why". Governments have their reasons for keeping secrets, stupid as those reasons may be. It really doesn't matter if aliens really do exist.

By the way, if aliens did exist, most likely they live among us, having technology that allows them to blend in with us or perhaps even control our perceptions. Thus it wouldn't really be our government hiding aliens. It would be the aliens hiding the aliens. Maybe every high-level politician inevitably gets replaced by an alien drone. I've got far too many alien invasion movies in my head right now (especially V). Again, however, none of this would matter. If aliens were responsible for hiding themselves among us, then there's absolutely nothing that we can do about it. At least until a noticeable crack in the system appears and the existence of aliens becomes plain to see.
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