Anyone who looks at the data does. Here's some: http://www.tradingeconomics.com/mexico/balance-of-trade
For the last several years, Mexico, for instance, has imported more goods and services (Measured in US dollars) than it has exported. (Their trade balance swung into positive territory just this year because of oil prices.) This means that during the last several years, more jobs were created in the US due to the free trade agreement with Mexico than were created in the US.
That’s one part of a larger story.
The net imports vs exports show that year after year the US is the big loser in jobs.
And a great part of our exports are agricultural products which are not big jobs creators.