For many years, the Justice Department has tried to break up large firms like IBM, Microsoft, and most recently Google, on the grounds that their...

For many years, the Justice Department has tried to break up large firms like IBM, Microsoft, and most recently Google, on the grounds that their large market share made them essentially monopolies. In a global market, where U.S. firms compete with firms from other countries, would this policy make the same sense as it might in a purely domestic context?