Jeff,
I would not call your last paragraph misleading. It is quantum mechanics—as opposed to quantum field theory—and I think QED is a gratuitously complicated way to answer the question. Perhaps it’s a way to get from classical notions of particles to quantum mechanics, but it seems to me to go against the spirit of trying to understand QM on its own terms, rather than as a modification of classical particles.
Jeff, I would not call your last paragraph misleading. It is quantum mechanics—as opposed to quantum field theory—and I think QED is a gratuitously complicated way to answer the question. Perhaps it’s a way to get from classical notions of particles to quantum mechanics, but it seems to me to go against the spirit of trying to understand QM on its own terms, rather than as a modification of classical particles.