That is rejected by history. Offshoring is a relatively new thing arising out of loose trade policy in a time when people snicker about treason, sedition and subversion as though it's the in thing. Apparently, Republicans have decided to emulate Sean Connery's character from "the Russia House" For the common good, everyone apparently must betray their country - and their common sense. The US seems to have had to pay prices for it's "affluence" since when.. since it started having to "pay for taxcuts".. Or since every candidate on all sides became globalists by limiting the competition to elitists who think only they have the pedigree to rule..
Well, no. The US has always paid a price in the form of taking risks and working long and hard. Interestingly, the industries engulfed by unions have faltered because those concepts were negotiated out of the job description. Your situation, on the other hand, is the result of increasing knowledge worldwide. As technology advances, the once esoteric and valuable roles become routine. The technology and skill I use to navigate Free Republic would have been damned near magic 20 years ago. In my own office, I do the work that used to take 3 or 4 secretaries PLUS the professional.
"Offshoring is a relatively new thing???" Uh... you may want to read up on some history. "Offshoring" is just a conjured-up epithet for trade, and foreign trade in both goods and services -- and therefore jobs -- goes back nearly to the dawn of civilization. Check out the first volume of Will Durant's history of everything.
Of course, trade and its concomitant creative destruction will always result in individual dislocations. My current hometown used to be an industrial powerhouse, and the local news is chock full of complaints like yours. The union mentality (which matches your rhetoric perfectly) persists, but it was that mentality that made this town into a shuttered-up post-industrial nightmare. But my former hometown down near Atlanta is a NEW industrial powerhouse, because the folks there compete in the new economy. And fooey on all these arguments that you can't make money at manufacturing -- everyone at my old plant was making a killing at base-level manufacturing. We just did it really, really well. My company transferred me to try to manage the plant I'm in now into this new mindset, but as you show very well, the entitlement mentality is a tough thing to uproot, and I doubt very much my current plant will be around much longer. It can't compete because of the old-school ways of our local employee base.
Manufacturing output is pretty constant in the US -- but it employs fewer people as we get better and better at it, and it's less of our economy because we as a nation can afford more and more services as we get richer and richer.
Your fairy world where a country can put up trade barriers and pay its people wages far beyond what the world market will bear doesn't exist, never has existed, and never will exist. Europe today is a good example of what happens when you try it -- you wind up with 30% of your "working" population doing nothing, and the rest headed that way, while your economic "growth" becomes nil.
We can either compete with the world, or whine about "unfairness" while we wither and die. Our economic figures say we're competing like gangbusters. God bless America, and God bless the invisible hand of the world market in everything.