After WW 2, the United States ruled the roost. A dozen years later in the late 1950's, parts of the world retooled. The United States was slow to that. The steel and automobile unions would threaten strike and strike if needed. The steel industry went first. It took 2 gas crises in the 1970's to slay the auto industry. Pittsburgh tended to do somewhat better than Detroit after deindustrialization. The rust belt has a lot of casualties. The electronic industry went next. Many who were employed got good pensions and a good buyout from corporations that moved overseas. We peaked around 1970 or so. We went from a creditor nation to a debtor one and lost control of the fiat currency.I worked in a steel mill for 35 years and the reason they`re in business today is that they always kept up with the new technology and production methods. Hundreds of jobs disappeared but they went by way of attrition and the USWA never opposed upgrades. We shipped our high tech alloys to dozens of countries where they didn`t upgrade. Other countries have cheaper labor but a lot more employees producing the same number of tons.