Does that matter? If two people independently invent the same thing, they're both inventors with equal standing. The classic example being Leibniz and Newton with regards to calculus of infintesimals.

Apparently it matters to the good people of Marshall, Texas. According to them, Whitfield Diffie didn't invent public key encryption for exactly that reason.

Yeah, I'm more than a little bitter about the technologically illiterate being allowed to judge complex technology.

Isn't it a given that they did? They strengthened DES's s-boxes against it 10 or so years before it was publicly discovered iirc.

You're right, that's precisely why they changed DES.