It's 2016 ... and the National Highway Traffic Safety Administration (NHTSA) just now approved a rear-view mirror that uses cameras. And they only approved it because it was a combined mirror/camera.
Let's get one thing out of the way right at the start: cameras and video screens readily available for at least the last ten years are unequivocally superior to a plain glass mirror. They have wider fields of view, they're unaffected by the placement of windows or interior obstructions, they see better in both low and high light situations. In addition to those safety considerations, they eliminate the safety problem (to pedestrians) and aerodynamic problems of external mirrors. They're better in every way.
But car companies are not allowed to build them into cars. Not allowed.
You can add one to your own car if you'd like, though. No problem with that.
Even if you believed (which I do not) that a government bureaucracy should be regulating something like a rear-view mirror ... it's still unconscionable that the NHTSA is taking so long to approve these things. If anything, they should have mandated rear (and side) view cameras years ago. It's as though some government agency required the use of vacuum tubes in radios, or vinyl records for your music.
Man, I really loathe big government. It blocks progress in so many stupid and costly ways...