09/15/2010 06:47 pm ET Updated May 25, 2011

The Connection Between Deficits and Foreign Policy

"Only connect" reads the epigraph to the English writer E.M. Forster's 1910 novel Howard's End. Forster's admonition is the basis of the book that I have just published, one hundred years later, entitled The Frugal Superpower: America's Global Leadership in a Cash-Strapped Era. The book connects two important public issues: America's growing debt and American foreign policy. Each of them is widely discussed but the connection between them is almost never made. The Frugal Superpower explores that connection and its consequences.

In recent months America's large annual budget deficits and growing national debt -- the sum of those deficits -- have received increasing attention. A bipartisan national commission has been formed to address them and both political parties routinely decry them -- although neither has proposed a credible plan for actually reducing them. The indebtedness of the United States will be a major issue in this November's midterm elections. Similarly, there is no shortage of interest in American military operations in Afghanistan and Iran, and American policy toward Iran, China, Russia, and other countries.

The discussions of these two sets of issues take place in isolation from each other, but they shouldn't, because the first will determine the second. Some day soon the deficit will in fact have to be reduced. At that point Americans will have to pay more -- perhaps much more -- in taxes and will receive fewer -- perhaps far fewer -- government services. In these circumstances, the American public will not be willing to pay for the kind of far-flung, expensive foreign policy that the United States has conducted for almost 70 years. Deficit reduction will limit what the United States does in the world.

The first part of The Frugal Superpower explains this crucial connection. The second part explores the likely effects of the looming economic constraints on American foreign policy around the world: in Afghanistan, Iraq, Europe, East Asia, and the broader Middle East. This survey of the global impact of a cash-strapped America, wide-ranging though it is, has a common theme: a reduced American foreign policy will be, on the whole, bad for the rest of the world.

Given all the objections to various American international initiatives in recent years, this may seem a surprising conclusion. But the United States plays, for the most part, a constructive global role, and to the extent that that role shrinks, other countries, even those most critical of what America does abroad, will suffer.

Take East Asia. China has made no secret of its resentment of the American military presence in that region, which helps to protect Taiwan, the island that the government in Beijing asserts is part of China and that it therefore has a right to control. Yet the Chinese would be unhappy at the withdrawal of American naval and air power from the Asia-Pacific region if this were to cause the countries there that now enjoy American protection -- Japan and South Korea as well as Taiwan -- to decide that they compensate for the missing American forces they must acquire their own nuclear weapons. China does not wish to live in a nuclear-armed neighborhood, but that is what the retreat, because of domestic economic pressure, of American power could well produce.

As I show in The Frugal Superpower, as the fiscal problems and the foreign policy of the United States become ever more closely connected in the years ahead, China, and other countries, will discover that there is one thing worse than an America that is too strong: a cash-strapped America that is too weak.

Michael Mandelbaum is the Christian A. Herter Professor of American Foreign Policy at The Johns Hopkins School of Advanced International Studies in Washington, D.C. His new book, The Frugal Superpower: America's Global Leadership in a Cash-Strapped Era, is published by PublicAffairs.