Not necessarily ..... Stealth technology is basically just a way to evade radar, which ppl have been doing since the invention of radar...whether it be a radar detector on your dash to avoid getting a speeding ticket or a way of hiding vehicles in combat, as radar becomes more sophisticated so does the methods of evasion....like anti virus programs, someone makes one to catch viruses and someone else builds a better virus...just a cat and mouse game....anything built can be reverse engineered to be defeated.....
My question is, if this stealth technology came from alien craft then why do u.f.o.'s show up on radar so often.