By 1979, the superiority of NATOs nuclear arsenal - both qualitative and numerical - was mainly based on nuclear artillery delivery systems that were able to fire smaller nuclear warheads at enemy forces on the battlefield with much more precision that the Warsaw Pacts technology allowed.
I thank President Reagan for a great many things but he had not yet been elected "by 1979."
I assume you are referring to his courageous installation of nuclear cruise missiles in Western Europe, despite literally millions of varmints shrieking and parasites screaming in the streets of Paris and West Berlin.