In what way? I actually contend the opposite, international trade helps most people. The less paid for an item the more money people have. That money can be used to buy other items, pay down debt, or be invested. Of course, until recently, people here in the US lived beyond their means. They continuously borrowed money the buy more stuff.
As for Walmart/Sam's, Walmart now has stores in China. And Chinese make enough money to buy from Walmart, as well as upscale stores. I don't recall what newspaper it was but one reported the first week Apple's new iPhone was available in China more than 1 million were sold there. Seeing as Apple products are only affordable to the wealthy, there are a lot of wealthy people in China. And those people buy American products sending money to the US. Another American company making money in China is Caterpillar, which builds construction equipment in Indiana employing thousands of people. John Deere based in IL does business in Brazil, China, and around the world. There are many other US based multinational businesses who also are in Brazil, China, India, and Russia (BRIC) helping employ more American workers.
And without international trade you would not be using a PC, or a cell phone. The US does not have a ready supply of a number of metals used to make these products. A major source of Coltan, columbite–tantalite, is Congo. Unfortunately it's mining fuels the conflict there.
GE leads a call to develop rare earth minerals in the US to reduce our dependence on Chinese suppliers. If China wanted to it could shutdown a number of US businesses by stopping exporting these minerals ton the US.
So who's the jerk?
Falcon