> A basic understanding of group theory lets you invent RSA, a practically-unbreakable asymmetric cryptographic scheme, given only the idea that
And I bet the NSA would break your homegrown RSA built with your basic understanding of group theory in a few minutes. RSA is extremely subtle to implement correctly and if you get it wrong you can easily leak everything.
Unlikely. The hard part of implementing RSA is making it secure against timing attacks, but I doubt my desk calculator and I will be particularly vulnerable to that. It's not like I'm going to suffer from the ECB penguin issue: MY MSGZ R SMOL and my key size is large enough to avoid that.
RSA really is very simple group theory. It was independently invented at least three times, as I recall.
And I bet the NSA would break your homegrown RSA built with your basic understanding of group theory in a few minutes. RSA is extremely subtle to implement correctly and if you get it wrong you can easily leak everything.