if china wants to believe it is unbreakable and the US can break the inscription you can bet we will not hear about it from the government.
That used to be the case. Now, with all of the leaks, I wouldn't be so sure.
Yeah, Let them keep thinking it is unbreakable. That was the way we intercepted German and Japan codes during WWII. It turned the German U-boats ability to sink our convoys. It gave us early warning of Japanese plans for the battle of Midway. That is just two examples of letting our enemies think their communications are secure.