Suppose I take your claim that "only the NSA could break [it]" on good faith. You're missing the word "presently." That back door is there. Others not having

Suppose I take your claim that "only the NSA could break [it]" on good faith. You're missing the word "presently." That back door is there. Others not having figured out how to interact with it yet is a matter of security through obscurity[0], and the system is still weaker for it, even though it's not yet fully cracked. [0] https://en.wikipedia.org/wiki/Security_through_obscurity https://en.wikipedia.org/wiki/Security_through_obscurity