Richard N. Cooper defends global imbalances in the JEP:

I argue that the generally rising U.S. trade deficit over the last 10-15 years is a natural outcome of two important forces in the world economy — globalization of financial markets and demographic change — and therefore that the U.S. current account deficit is likely to remain large for at least a decade. In a globalized market, the United States has a comparative advantage in producing marketable securities and in exchanging low-risk debt for higher-risk equity. It is not surprising that savers around the world want to put a growing portion of their savings into the U.S. economy. I argue that serious efforts to reduce the U.S. deficit, even collaborative efforts with other countries, may well precipitate a financial crisis and an economic downturn every bit as severe as the one that many fear could result from a disorderly market adjustment to the trade deficit.

While Martin Feldstein disagrees:

I believe that such enormous deficits cannot continue and will decline significantly in the coming years. This paper discusses the reasons for that decline and the changes that are needed in the U.S. saving rate and in the value of the dollar to bring it about. Reducing the U.S. current account deficit does not require action by the U.S. government or by the governments of America’s trading partners. Market forces alone will cause the U.S. trade deficit to decline further. In practice, however, changes in government policies at home and abroad may lead to faster reductions in the U.S. trade deficit.