The headline is pretty scary: “China’s Quantum Computer Scientists Crack Military-Grade Encryption.” No, it’s not true. This debunking saved me the trouble of writing one. It all seems to have come from this news article, which wasn’t bad but was taken wildly out of proportion. Cryptography is safe, and will be for a long time EDITED TO ADD (11/3): Really good explainer from Dan Goodin.
Yep. Technically you could in principle use Grover’s algorithm to speed up cracking a symmetrical cipher, but the size typically used for the keys is too large so even though it’d technically be faster it still not be possible in practice. Even with asymmetrical ciphers we already have replacements that are quantum safe, although most companies have not implemented them yet.