There are some good comments here, thanks! There has been an international component to physics research cooperation. It seems not inconceivable that physicists in many countries, meeting at paper conventions and such might have agreed and recruited each other to try to prevent the next atomic bomb type invention. So while competition between countries is certainly real, competition between scientists might be somewhat different. You'd think there would be some people who would pursue it regardless, but they'd probably have to work with a team, and not everyone on the team may have supported the goals. It's just a theory, but it has some plausibility. Perhaps there are people everywhere who have decided not to be part of endeavors that could be disruptive and they've done us all a favor or have kept us from discovering the secrets of the universe. Who knows? The ethics of science has been mostly left to chance and individual decisions.