Despite the East-West territorial clash over the buffer state of Ukraine, despite the sanguinary battles for patches of ground across the swath of the Middle East -- in Libya, Yemen, Syria and Iraq -- and despite the zero-sum territorial conflicts throughout maritime East Asia, the myth persists of a world benignly ruled by multilateral institutions and agreements, by international financial markets that have all escaped geopolitics, and by the geography on which it is based.

Such thinking obviously contains a large measure of truth, but taken too far it creates the dangerous illusion of inexorable progress that is willfully blind to dangers ahead. While geography tells many stories, often contradictory, and can be overcome by human agency -- especially in the form of brave and moral leadership -- a belief in the inevitability of progress is dangerously deterministic. It was such deterministic optimism that made the civilized world less prepared for the two world wars in the 20th century.

As long as the world is ruled by imperfect men and women -- some of whom will be evil, some of whom will be naive and some of whom will be competent yet unable to avoid disputes with other competent leaders whose self-interests and national interests are simply different -- conflict will dominate international relations. And as long as human beings live on this earth they will have disputes over territory that, no matter how bleak or water-starved or lacking in other resources, constitutes holy ground fundamental to their group identity.

This situation will be aggravated by the world population increasing from 7 billion to more than 9 billion by 2050, according to the latest U.N. projections. Most of this increase will occur in the poorest and least stable countries -- those already prone to war. Geography is about to become more precious than ever. Meanwhile, communications technology will make geopolitics increasingly claustrophobic, as events in one part of the world can affect those in another as never before.

Interlocking, catalytic conflict rooted in geography is about to define the 21st century. To wit, Europe lacks the will to enforce meaningful sanctions against Russia because it is too dependent on Russia's webwork of natural gas pipelines -- a fact of geography if ever there was one. This leads to a perception of weakness on the part of the West that can only encourage the Chinese to be even more provocative in pressing territorial claims in the South and East China seas. The Japanese, who contest territory in the East China Sea with China, have specifically warned of the danger that the Western response to Crimea poses to them.

Meanwhile, the collapse of distance wrought by advances in military technology has brought China and India into a strategic competition that has no precedent in their collective histories: Indian space satellites spy on Chinese airfields; Chinese fighter jets have the capability to incorporate India into their arc of operations; Indian missiles can target Chinese cities and Chinese warships are present in the Indian Ocean. The world has shrunk, in other words, even as vast and poverty-wracked cities expand, and group identity -- whether tribal in Africa, sectarian in the Middle East or ethnic and nationalistic in East Asia -- has been dangerously reconstructed by the Internet and other technologies into the most exclusivist, inflexible forms.

But what about all those new global and regional institutions and organizations, to say nothing about the growth and opportunity that has come from financial markets? Aren't they the other, more positive half of reality? They are. But then the question arises: Why have they been able to come into being in the first place? What ultimately undergirds them? The answer is one that many members of the global political and financial aristocracy do not want to hear: raw American power.

Because the American economy is the world's largest, and because the American people have over the course of the decades agreed to employ that prosperity in service to an immense military armature across the globe, stability, such as it exists, and a new and unprecedented global civilization have been able to emerge. Take away that raw American power -- which is first and foremost a geopolitical phenomenon -- and the escape from geopolitics that many proclaim suddenly evaporates.

It is the various U.S. Navy fleets and numbered air forces that are the ultimate guarantor of stability in the key theaters of the globe. The U.S. Seventh Fleet, because it can easily defeat any rival, keeps the peace of East Asia. The spectacular Asian economic boom that commenced in the late Cold War decades is simply impossible to even imagine without the security provided by the U.S. military. Take away the Seventh Fleet and the chances of China and Japan going to war increase dramatically, roiling financial markets in the process. It is the Seventh Fleet that still stands in the way of China being able to Finlandize South Vietnam, the Philippines, Malaysia, Singapore and Indonesia. Wide stretches of the Middle East may be in chaos or semi-chaos, but it is U.S. air and sea power that helps prevent a Persian Gulf war between Iran and Saudi Arabia and provides ultimately for the security of Israel and Jordan. As for Europe, without U.S. military power Russia is more dominant than the European Union on the Continent, and the independence of the Baltic states, Poland and Romania is crushed or dramatically diluted. Geography certainly matters, and Europe's freedom survives best because of the geographical breadth of the U.S. military.

The United States is not a traditional empire because it has no colonies, but its military -- and the diplomatic power that accompanies it -- is deployed in an imperial-like fashion worldwide. The U.S. Navy calls itself a global force for good. That claim would pass the most stringent editorial fact-checking process. Without that very naked American ambition, which allows the Navy and the Air Force to patrol the global commons, the world is reduced to the sum of its parts: a Japan and China, and a China and India, dangerously at odds and on the brink of war; a Middle East in far wider war and chaos; a Europe neutralized and emasculated by Russian Revanchism; and an Africa in even greater disarray. It is not that regional powers cannot act rationally on their own; it is only that without a global hegemon of sorts, local balance-of-power interactions become more fraught with risk and are, therefore, more dangerous.

The 1914 scenario that many proclaim for both Europe and East Asia would become much more than journalistic hype absent American military preponderance. The spread of democracy that many celebrate would be impossible to imagine without the American military's global footprint since, if you project your power, your values will often follow behind you.

It is true that the early 21st century is different from the 20th and 19th centuries. It is different not so much because of a change in human nature, or because of postmodern technology, or because of the disappearance of geopolitics. To the contrary, it is different because the United States, with all of its limitations and all of its mistakes, remains geopolitically dominant.

Great powers are rarely appreciated in their own time, for the benevolent order they spread goes unacknowledged by those who benefit most from what they provide. Global civilization -- and the system of legal norms that arises from it -- survives to a significant extent because the American military remains robust and widely deployed. And that, in turn, is not a situation that is necessarily permanent, or one that can ever be taken for granted.