In an article in Esquire early in 2003 Tom Barnett, a professor at the Naval War College, outlined a proposed "grand strategy" for the twenty-first century, based on the concept of "The Functioning Core and the Non-Integrating Gap." "The Core" refers to those nations with relatively stable governments and a willingness to cooperate in a more or less peaceful world community. This included the United States, Japan, most of Europe (though not the Balkans), and Russia, plus a few nations in other areas, such as India, Argentina, Brazil, Chile, Australia, New Zealand, and the Asian "Little Tigers," as well as China, essentially the "globalized" community, roughly two-thirds of humanity. In contrast, "The Gap" was the region of instability and poverty that has been largely failed to integrate into the global community, including large swathes of the Americas, the Balkans, most of Africa (save South Africa), the Middle East, and Central and South East Asia. This latter area, encompassing about a third of humanity, he observed, has been the scene of far more military clashes, internal upheaval, poverty, and brutal oppression, while being a focus of international terrorism, which it exports to the rest of the world. In essence, Barnett proposed that the "Core" nations – led by the United States, acting as much as possible in cooperation with other "Core" states and under the umbrella of the United Nations -- undertake to stabilize the "Gap" and help bring it in to the globalized community.

In The Pentagon's New Map, Barnett elaborates upon this grand strategy, a formula for the next few decades that can be likened to George Kennan's famous 1946 "X" article, "The Sources of Soviet Conduct," which outlined the "Containment" strategy that ultimately won the Cold War . The book essentially has two themes.

First, Barnett notes that the events of 9/11 essentially "saved" the Pentagon from its fixation on the Cold War. A decade after the collapse of the Soviet Union, despite the total absence of any power capable of threatening the U.S. conventionally, the Department of Defense was still focused on "The Big One," and wholly unprepared for what has come to be call "asymmetrical threats." The events of September 2001 forced a reluctant military establishment to find ways to cope with a new kind of warfare, one in which the nation's massive conventional – and even nuclear – capabilities was of little use, in a transformation that is still in progress.

Barnett goes on to say that Bush Administration "has the right strategic vision" and has taken many of the steps needed to get a long-term strategy rolling." He faults the administration, however, in failing to explain this strategy to the American people and to the global community. The essence of the "Core/Gap" strategy is that while there is an established and generally smoothly-running international security system in the "Core" different rules are necessary when dealing with the "Gap." In these terms, the policy of "pre-emption" applies to the "Gap", not to the "Core", where there are numerous alternative approaches to resolving problems, and a generally mutual-willingness to do so. The result of this failure to effectively articulate the strategy has been an enormous amount of ill-will and acrimony both domestically and internationally, which came very near to destroying NATO. Barnett wraps up his discussion by outlining some of the dangers of a forward policy towards the Gap, such as becoming embroiled in internal and regional quarrels. And he concludes by stressing the need to maintain the integration of the "Core" nations, lest they lose a sense of commonality, leading to fragmentation into regional power-blocs, with the result that the Core will not only fail to grow, but will leave the problems of the Gap unaddressed and result in a more unstable world.

An important contribution to the debate on the nature of conflict in the twenty-firs