No, he's saying that the number of manufacturing jobs has dropped in the US, in Mexico and in China.
they may have gone to mexico, meanwhile existing jobs in mexico went somewhere else.
Since NAFTA Mexico has lost about 250,000 manufacturing jobs mostly to Asia.
But the biggest destroyer of manufacturing jobs worldwide has been the evil monster called "Productivity"
Manufacturing productivty grows about 8-10% annually, but demand is growing at most 4%, that creates a huge redundancy of manufacturing jobs worldwide.
What matters isnt employment, that is the wrong way to measure manufacturing, it is output. By that measure manufacturing in the US has bee nremarkably stable over the past 25 years.
BTW are you are that over the past 100 years farming employment has fallen by 90%??? Are you starving???