Do you think it is safe, for say, a non certified (read: a guy with no CS degree) programmer to design and code software that runs on an MRI machine ? Or the one which controls airplaines ? If airplaines start crashing because of a software fault, do you think we could and should blame the programmer for not having made the required tests ?
Software _development_ is a very young discipline, and as such has not yet been regulated. But I believe the day will come where it will.