Pennsylvania, once the Workshop of the World, where big factories made big stuff, is now America's Warehouse, where shippers import goods through Eastern ports and send them out via free Interstate highways to points South and West.

Wal-Mart says it will open "its largest ever" warehouse in Bethlehem, Pa., in the Spring, and hire 350 workers to ship electronics, toys, guns and other popular items. Liberty Property Trust says it has leased to Wal-Mart the newly-completed 1.2 million square foot facility at 2785 Commerce Center Blvd. says it will hire 70,000 new workers to ship Christmas orders through its warehouses in Pennsylvania, Delaware and 10 other states. Amazon has warehouses in Carlisle, Hazleton and Lewisberry (Lehigh Valley), Pa. -- more than any other state except Indiana and Kentucky -- and two more in Middletown and New Castle, Del. Amazon will hire "thousands" of seasonal workers for both the Pennsylvania and the Delaware sites, spokeswoman Kelly Cheeseman told me.

Why Pennsylvania and Delaware and not, say, New York or New Jersey? "There are a lot of factors," Cheeseman said. "Mostly, to be close to our customers. But also, secondarily, things like workforce. We've found tremendous talent in Pennsylvania." In central Pennsylvania, at least.

The Amazon jobs in Pa. pay up to $13.50/hour in Hazleton (via Integrity Staffing Group) and $12.75/hour at the other two Pa. sites, which are among Amazon's top wages at "fulfillment centers." The Delaware sites pay up to $11.50/hour. Amazon locations in Kansas and Kentucky, by contrast, advertise only up to $11/hour.

Wal-Mart, like other store-based retailers, is trying to boost its warehouse operation so it doesn't end up like Borders, Best Buys and other victims of Amazon's low prices and universal shipping.