Source. I found it in about 2 minutes. I would say “OP should have done the same instead of reposting this” but actually I can’t find this image anywhere and it may be an original screenshot.

Anyway, here’s the letter:

I saw several variations on this exact meme over the last days, and it is so insanely idiotic I’m halfway to thinking it’s some sort of psy-op. Personally, I like shitting on conservatives as much as the other guy, and… do I really need to explain that one can’t simultaneously talk about Haha How Dumb Those Guys and also call yourself open-minded? The moment you do the former you have given up on the latter.

This is a rather reductive view of quantum cryptography. The two most common applications of it I hear about is the development of encryption algorithms resistant to being broken on quantum computers (the way, say, Shur’s algorithm is known to break RSA) and techniques like quantum key distribution. Both of these are real problems that don’t become meaningless just because one-time pads exist - you need to somehow securely distribute the keys for one-time-pad encryption. That’s why one-time pads aren’t used everywhere (“it would cut the whole internet bandwidth in half overnight” would not have been a sufficient reason - that’d be a tiny price to pay for unbreakable encryption, if it actually worked).