The Northeast actually began its decent into irrelevance in the 60’s, with the decline of Route 128, IBM, and basically the entirety of upstate NY, which was once a high-tech and industrial powerhouse (hard to believe, but true).
When I was a kid, most TV/radio originated in NYC.
Bottom line, the country’s center of gravity has moved southwest, and there’s very little that the NE can do about it, except change, which they won’t.
M*A*S*H portrayed Charles Emerson Winchester as a crusty, rich, conservative from Back Bay (Boston). My how times have changed...except for the “rich” and “crusty” parts. :-)
Yes. Unionization drove all of that sort of manufacturing to Japan. In 1960 electronics was all the rage and there were hundreds of US companies with names that ended in -ion or -eon. Today only one company, Raytheon, survives from that era.