When a Walmart opens, it knocks out about half the jobs in a small town. It doesn't replace that number. It also pays so low many of its employees are on welfare. Companies like WalMart are subsidized by the taxpayer. Repeat that across thousands of stores to get enormous impact on economy.

Add downsizing, consolidation, price gouging (i.e. Koch's, oil), and offshoring to get an even bigger one across the board. The Recession was a given with buying power always going down while costs always go up.