I’m not in the industry, but I would say Hermeus would be a perfect example. Ostensibly building a commercial airliner, but if you look closely it feels like a military oriented startup from the inside out.

Google tried to become a national security contractor, and the backlash among the engineers was very intense.

Can't give any examples but I have definitely heard the same about a lot of aerospace startups through the grapevine. As for OP's point about private jets, Boom supersonic is your classic example.

I can't name names but 3 of the startups I've worked at.

Places I haven't worked:

Skydio

Applied Intuition

Saildrone

Planet Labs

Boom

Scale AI

Also worth noting that sometimes it's on purpose, sometimes the founders are all "we're gonna save the world" then AFWERX enters the chat with a big fucking check and the founders yell "Nevermind! Guess we're the baddies now! How many slaughterbots did you say?"