Quantum Threats to Cryptography

They can't hash SHA256 with this quantum computer, can they?

Are these quantum computers currently powerful enough to tackle things like breaking non-quantum proof encryption?

Wait, so can quantum computers now crack public key cryptography, or not?

Algorithms have been developed for quantum computers that could be potentially effective at breaking public key cryptosystems whose security relies on the difficulty of solving certain math problems on classical computers. In particular, the discrete logarithm problem and integer factorization of very large numbers: https://en.wikipedia.org/wiki/Shor%27s_algorithm.T

Who can break crypto with quantum computing? That is total speculation.

I guess quantum computing breaking it and them not being fast enough to adapt

To address just one of your points, quantum computation is not a silver bullet. It does not work the way one might think it works. Not many researchers are saying that they will replace classical computers, and for good reason. For many, or even most, computational tasks there is no way to get a large quantum speedup. (And classical computers have had a lot more R&D put into them.) Although easy integer factoring will break quite a few popular crypto schemes, like RSA, the risks of quantum c

SHA is not crackable with quantum computers. RSA and Diffie-Hellman are though and nobody has done it yet (or come close).

Not all existing crypto would be broken. Symmetric encryption algorithms like AES will be fine. Asymmetric encryption (public-key) algorithms like RSA/DSA will be in trouble due to Shor's algorithm, but other public-key systems will be fine. Hash functions like SHA-2 and SHA-3 will be mostly fine, because Grover's algorithm is at best sub-exponential, not quadratic.Also, quantum cryptography mostly provides superior key establishment/management capabilities, not superior c

Shor you can: can it break RSA? If yes, QC. If not, not QC.