I DON’T often read the conservative columnist Ross Douthat in the New York Times, but a week after the Obama administration’s assassination of Osama bin Laden, Douthat for once made an astute observation:

For those with eyes to see, the daylight between the foreign policies of George W. Bush and Barack Obama has been shrinking ever since the current president took the oath of office. But last week made it official: When the story of America’s post-9/11 wars is written, historians will be obliged to assess the two administrations together, and pass judgment on the Bush-Obama era.

This is not exactly what most of Obama’s supporters had in mind when they voted for him in 2008, but two-and-a-half years later, the record speaks for itself: Large numbers of U.S. troops still in Iraq and likely to remain there beyond the supposed withdrawal date later this year; an expanded war in Afghanistan, with regular attacks across the border into neighboring Pakistan and high numbers of civilian deaths; a secret bombing campaign in Yemen exposed by Wikileaks; and an open bombing campaign against Libya and saber rattling against Iran. U.S. imperialism did not end when George Bush left office.

Marxists have long argued that imperialism—the effort by the biggest economies to dominate the world and outmaneuver their rivals—is not a policy, but something built into the fabric of developed capitalism, as economic competition gives rise to geopolitical competition and military intervention. The form of that competition can change over time, but so long as capitalism exists, so will imperialism. That is why—apart from minor differences—both major political parties in the United States pursue the same foreign policy agenda.

V. I. Lenin and Nikolai Bukharin, two of the leaders of the Russian Revolution, developed the classical Marxist theory of imperialism almost 100 years ago in the middle of the First World War. In his short book Imperiaism: the Highest Stage of Capitalism, Lenin wanted to show how the imperialist expansion of the major world powers in the late-19th and early-20th centuries was rooted in profound changes in the nature of capitalism during the same period. “If it were necessary to give the briefest possible definition of imperialism,” he wrote, “we should have to say that imperialism is the monopoly stage of capitalism.” Lenin’s argument was that the rivalries and wars between the capitalist powers were inherent in one of capitalism’s basic features: the tendency for capital to become more centralized and concentrated—in other words for the dominant capitalist firms to become fewer and bigger.

Bukharin analyzed this process more systematically in Imperialism and World Economy. He argued that imperialism is the result of two contradictory tendencies that exist in modern capitalism. Competition tends to give rise to the concentration and centralization of capital. As this process develops there is a tendency for the state to play an increasingly active role in managing the economy, and ultimately, he argued, for capital and the state to merge together to form what he called “state-capitalist trusts.”

But at the same time, there is a tendency for production, trade and investment to break out of national boundaries and to become organized on a global scale. So, according to Bukharin, there are simultaneously contradictory tendencies towards greater national control of the economy and towards greater internationalization. Bukharin argued that as a consequence of these two tendencies, economic competition between capitals was increasingly being expressed as geopolitical competition—political and military rivalries between states for territory, influence, and power. This is the basis of imperialism.

Bukharin sometimes described the tendency towards the creation of state-capitalist trusts as more complete than it really was, and he wrongly believed that such trusts would only be affected by outside crises, ignoring the internal contradictions that continued to exist in all capitalist economies. On this score, Bukharin needs to be modified by Lenin, who noted, “When monopoly appears in certain branches of industry, it increases and intensifies the anarchy in capitalist production as a whole … At the same time the monopolies, which have grown out of free competition, do not eliminate the latter but exist above it and alongside it, and thereby give rise to a number of very acute antagonisms, frictions and conflicts.”

There is one other important element in this theory. Capitalism tends to create a single world economy, but development does not take place uniformly either within individual states or in the system as a whole. Instead, it is characterized—in Trotsky’s famous phrase—by combined and uneven development. Economic, military and political power tends to be concentrated in a handful of states, which therefore dominate the rest of the world. But, as Lenin noted, “the differences in the rate of development of the various parts of world economy” were increasing. In certain circumstances it is even possible for relatively backward states to develop rapidly by importing advanced technologies.

This is crucial, because it shows that the division of power between the advanced states and the rest of the world isn’t static. Even if stability in international relations is established for a period of time, it would eventually be undermined as the result of economic changes that weakened some powers and gave rise to new powers that would seek to play a bigger role in world affairs. Periodically the new economic alignment of forces would give rise to diplomatic, political, and eventually military conflict that would reconfigure the balance of forces between the dominant nations. So, for instance, the attempt at the end of World War One to prevent the outbreak of further wars by creating the League of Nations was a complete failure. Within a few years sharp differences between the major powers reemerged and the world was engulfed an even more barbaric war.

LENIN AND Bukharin’s theory seems to fit the first half of the twentieth century, but after World War Two, the structure of global politics changed dramatically. Before the war, the world was economically and politically multi-polar. After the war it remained economically multi-polar, but became politically bipolar, with the formation of two rival global military alliances, one dominated by the United States, the other by the USSR. At the same time, a process of decolonization began, ending most direct control of foreign territory by the 1960s.

Wars continued on the periphery, and the superpowers engaged in a massive arms race, but there was no war between the two major powers, because the threat of nuclear escalation made them more cautious. Then with the collapse of the Soviet bloc between 1989 and 1991, the structure of the global system changed again, leaving the United States as the sole superpower.

Meanwhile, economic changes resulted in a reversal of the trend towards the greater integration of state and capital that Bukharin had described. Instead, over the past 30 years neo-liberalism has resulted in privatization of state-owned assets and much greater deregulation of the economy. Growing international integration of the economy weakened the ability of individual governments to manage and intervene in their own economies. Taken as a whole, these developments have led some on the left to conclude that the classical Marxist theory of imperialism is outdated.

In their briefly influential book Empire, for example, Antonio Negri and Michael Hardt downplayed the importance of nation states and described a world in which imperial domination was maintained by a much more decentralized network of multinational corporations and international institutions. According to Negri and Hardt, “no nation-state can today, form the center of an imperialist project.” Later they write,  “The history of imperialist, interimperialist, and anti-imperialist wars is over. The end of that history has ushered in the reign of peace. Or really, we have entered the era of minor and internal conflicts.”

But little more than a year after Empire was published in 2000, its central theses were refuted by events in the real world, as the United States engaged in a new and more aggressive phase of imperialist intervention in Afghanistan and then Iraq. The 9/11 attacks were used as the justification for these wars, but the real reasons for the projection of U.S. power ran much deeper.

One positive consequence of the Cold War for the United States was that it gave Washington political dominance over the major capitalist countries in Europe and Asia, since they depended on the U.S. military for their security. But with the collapse of the Soviet Union, Western Europe’s dependency on the United States decreased at the same time as its economic and political integration accelerated. Planners in Washington viewed this as a potential medium-term threat to continued American global dominance. Makers of U.S. policy also became increasingly concerned about the possibility of a German-Russian strategic alliance, and the emergence of China as a major economic and military power.

The Clinton administration responded to these challenges both economically and militarily. It pushed through policies of economic globalization designed to bind the other major powers into relations of dependency with the United States. Simultaneously, it followed a policy of strengthening and expanding NATO in order to maintain its presence in Europe and weaken Russia. This culminated with the interventions in Bosnia and Kosovo, intended to maintain European dependence on U.S. military power.

Strategists from both sides of the political aisle began to look for ways in which the United States could use its enormous military power to keep it main rivals in check. In a report issued in September 2000, the neo-conservative Project for the New American Century (associated closely with the Bush administration) outlined the key strategic goal as “maintaining global U.S. pre-eminence... and shaping the international security order in line with American principles and interests.”

Key to achieving this goal, according to the report, was seizing control of the Gulf region. “While the unresolved conflict with Iraq provides the immediate justification, the need for a substantial American force presence in the Gulf transcends the issue of the regime of Saddam Hussein.” Regime change in Iraq would not only give the United States control of the second largest oil reserves in the world, it would also strike a blow against Washington’s main rivals, particularly Europe and China, both highly dependent on Middle Eastern oil.

As Gilbert Achcar puts it: “September 11, 2001 came as a terrific windfall for the Bush administration…. The spectacular blow struck by Islamic fundamentalists, former U.S. allies who had become its sworn enemies, created such a huge political trauma in the United States that the Bush administration thought it was possible at last, for the first time, to break once and for all with the ‘Vietnam syndrome’ and return to the unbridled military interventionism of the first Cold War decades.”

THE SHIFT to a much more aggressive and unilateralist foreign policy was not the result of neoconservatives hijacking the government, but a consequence of radically new circumstances providing U.S. imperialism with the opportunity to solve its problems in a new way. But the world that U.S. policy has brought about over the past several years has created enormous new problems for the U.S. ruling class. The occupations of Iraq and Afghanistan have bogged the U.S. down militarily.  At the same time, regime change in Iraq strengthened Iran by removing its biggest rival in the region, leading to the sharp confrontation between Washington and Teheran.

Second, while Washington has been largely successful in reintegrating the countries of Western Europe into a U.S.-dominated international framework over the past few years, the same is not true for Russia (which is still a major military power, with thousands of nuclear missiles) or China (which is a rising economic and military power). Indeed, U.S. policy makers are obsessed by the rise of China and how they can prevent it from becoming a major challenger to U.S. power on a regional, or even a global, level.

The United States used 9/11 to set up a string of military bases in central Asia. Partly in response, Russia and China formed the Shanghai Cooperation Organization that for the past few years had been trying to reduce U.S. influence in the region. Africa, with its important oil resources, has also become a major center of rivalry between the United States, China and Russia, with the United States establishing AfriCom in 2007, a new military command for U.S. forces based in or near Africa explicitly intended to counter Chinese “power projection” into the region.

These are illustrations of the way in which the major centers of economic and military power in the world are maneuvering against each other for advantage. None of them are prepared to stand out against the United States directly, because the costs are too high, but it illustrates the fragmentation and instability of the global system.

This is inter-imperialist rivalry of the kind that Lenin and Bukharin talked about, even if war between the big powers is not a likely immediate prospect. It still means that the most powerful states will use their military strength in whatever ways they can to pursue their own interests, typically by intervening militarily in weaker countries, or threatening to intervene.

The U.S. ruling class is currently playing for very high stakes as it attempts to maintain its dominant global position in a world in which the distribution of economic power is changing to its disadvantage. That is producing a highly unstable and potentially very dangerous situation. Other leading powers may not be prepared to challenge the U.S. directly at the moment, but that doesn’t mean that they won’t be prepared to do so in the future. Unless we get rid of capitalism, the prospect of military confrontation in the future is very real.