Hitler won many wars because he had a strong offense, but ultimately lost because of spreading himself too thin and weakening his defense. Russia on the other hand wasn't conquered by Germany because they pulled back eveything and mouted a strong defense that Hitler couldn't defeat!
I'm thinking that just telling the world you have a weapon like the Stealth is a defensive tactic, and I guess that's why the U.S. announced we had it.
If you don't tell the world you have a great weapon... you could end up like this!
YouTube - Dr. Strangelove - 1964 Part 7/11