Over the last three decades, companies have established wide-ranging global supply chains that have taken advantage of steadily improving scale economies in global logistics. Efficient and reliable ocean and air cargo have linked low-cost manufacturing hubs across Asia with major markets in the United States and Europe. Much of this global sourcing was driven by the cost savings reaped through labor arbitrage, cost savings that were so dramatic that it more than covered the expense associated with moving products across vast distances to markets, or the extra cost of carrying inventory in long pipelines.