You overestimate the importance of Walmart for the US economy. Walmart does not produce ANYTHING. They simply buy in China and sell in the US. You could replace them with an online  Chinese import/export company and get the same effect... cheaper.
Infinite: I should have mentioned Ford and GM.
Ford and GM are both great examples of companies you don't want to work for... other's would be United and Enron. The problem with either of these is that management only cares about short term success to satisfy stock owners and has absolutely no long term strategy. The US does not need any more of these companies. Let them die... and make room for new players with better management. I do not care if they are called Toyota and Honda as long as they employ people, pay taxes and don't need to be bailed out every other decade.