Re: Custom made tools.
Not so, most of the 60,000 factories closed (that is the number being bounced around on the latest Pacific rim trade dealings) were that type of work. MOST machine shop work is now done overseas. The only small bit that isn't will be on-demand instantly needed work. Anything that makes parts that then go in a box to ship later can be made elsewhere. Why the plummeting wages, they wouldn't if the job could not be replaced.
Like my chosen trade, printing. Great chunks of it now done in China, but the last 15 years I was in 24 hr. turnaround work that had to deliver all over the US simultaneously by the next day. Financial work like for Wall Street, you can't move that to China at all. That kept my fat out of the fire while others were losing jobs left and right. Similar to the machinists, the pay scales have dropped, what I got paid $25+/hr. for, now around $12-$14 commonly now.