When Barack Obama was talking to about 200,000 Berliners during the United States presidential campaign in 2008, he said “that the problems of the world were too great to be solved by one nation alone”. Well, most of us always knew that. But Obama was recognising more than the United States’ need for the European alliance. He was acknowledging the profound, irreversible redistribution of power in the world that actually has far more to do with China and India than with the Europeans. History suggests a precedent for adapting diplomatic practice to such changes—a precedent to which Obama appears intuitively oriented.

The increased status of the G20 is a logical consequence of the interaction of those forces of change. It used to be just a talk-fest for the treasurers of the top 20 economies, but it now requires heads of government. The six great powers (the United States, China, India, Russia, the European Union and Japan), the eight major emerging powers (Brazil, Mexico, Argentina, Indonesia, Turkey, Saudi Arabia, South Korea and South Africa) and six long-established and usually prosperous Western powers (Germany, Britain, France, Italy, Canada and Spain) plus Australia make up a forum which will have an impact on future decisions about how to managethe crises of our multipolar and rapidly changing world. No other grouping takes most of the policy-makers concerned into so influential a company.

George Bush did not invite all the “possibles” to the November 2008 meeting. Later three or more other powers ought to qualify for the group (Iran, Pakistan and Vietnam), and it might in time become the G25. So, to define the overall power-distribution that appears to be emerging this century, it is a central group of the six great powers, a larger circle of at least 18 or so majorpowers, and an outer contingent of the remaining 175 or so other governments of the society of states. But even minor and middle powers in that third group have much more capacity than they have had in earlier centuries to upset the global apple-cart. The world saw that in the economic crisis of late 2008. Though Iceland has a smaller population than Canberra, and no armed forces,its bankers nevertheless seem to have managed (inadvertently) not only to have destroyed their own government but also to have damaged the finances of Britain. That made them, to my mind, surprisingly powerful non-state actors, along with their confrères on Wall Street.

During the second half of the 20th century, the international distribution of power, in contrast to the fast-changing present, was rather stable. Washington and Moscow, for the 43 years of the Cold War (1946–89) glowered at each other, across what often seemed an unbridgeable chasm. Then the Soviet Union fell apart, and we had the 10 years of the “unipolar moment”, of unchallenged US paramountcy. Now that moment has also passed into history. So it has become possible to ask ourselves what this new distribution of power (the context Obama must act in) means for the prospect of maintaining a reasonable degree of order, prosperity and democracy in the world—a very dangerous and crisis-ridden multipolar world, a world of a great many “unknown unknowns”.

Despite all its uncertainties, however, the working of world politics still largely depends on the distribution of power between sovereign states. The structure of diplomacy in the foreseeable years of the 21st century seems thus likely to resemble that of the 19th more than that of the 20th century, because the distribution of power internationally will resemble that of the period after 1815 more than the period after 1946. Then, at the beginning of the Cold War, there was a bipolar balance of power. Now, as after 1815, there is a viable but very much wider multipolar distribution of power. And that may become either a balance of power or (with luck and prudent, creative diplomacy) a concert of powers, as in the period 1815–1914, but on a vastly larger scale. Fortunately, the other forces whose impact we currently most feel, globalisation and climate change, seem likely to nudge the system towards the “concert” pattern, rather than the “balance” pattern, because both require the widest and most universal practice of international co-operation, and neither can be remedied by military operations.

A good many people in Washington seemed, until the election of Obama, either to mourn the end of the unipolar world, or to be still denying that it had happened. But the advent of a viable multipolar balance of power, based on a well-defined distribution of power, will have its advantages even for the United States though they may not be officially welcomed there yet. The unipolar world of 1992–2001 evoked numerous international resentments: even some of Washington’s traditional allies, such as France, resisted it. That phase (and the US triumphalism that unfortunately went with it) was still more resented by its past and prospective adversaries (Russia and China), and much of the Third World. The earlier bilateral balance in the 43 years of the Cold War (1946‑89) had made the adversarial relationship too sharp and direct to support much in the way of diplomatic consensus. A wider balance, with several kinds of capacity (economic, diplomatic, and strategic) distributed unequally, but with a tendency to deliver some degree of diplomatic clout to each power, may give all of them reasons to keep the system viable. Each of them has a stake in its preservation, because it offers real advantages to each of them.

The period 1815-1914 was the last phase of diplomatic history to see a viable and (until 1870) stable balance of power. The four victors of Waterloo at the end of the 12 years of the Napoleonic Wars (Britain, Russia, Prussia and the Austrian Empire) had no reason to ignore changing power-relationships. They knew that although France had been defeated, and had had a change of regime imposed on it, it would not stay defeated. So in 1818, only three years after Waterloo, they allowed it to join what became known as the Concert of Powers. That system of international governance lasted (fairly effectively most of the time) for 99 years, at least to the truly vital degree of enabling the powers to avoid hegemonial war, that is, war between the great powers to determine the fate of the world. The Napoleonic Wars, World Wars I and II and the Cold War were all of that status. The system did weaken considerably, however, for 17 years during the period of the Crimean and Franco-Prussian Wars, 1854-71, and fell in ruins in 1914 after Prussia had become Imperial Germany. So by 1918 it was widely dismissed as a failure.

But in the 99 years of its survival, the Concert of Powers had seen off many potential war-bearing tensions and rivalries. Britain and France had a bitter colonial rivalry in Africa which brought them close to war as late as the Fashoda Crisis of 1898. Britain and Russia had an equally bitter rivalry in Central Asia (the Great Game) which was not resolved until 1907. The fervours of nationalism were as great in the Europe of that time as they may be in the Asian future, though there were fewer major players in diplomacy than there are going to be in the diplomacy of this century. Aside from the five great powers, there were also about 10 major powers, including the United States and Japan, then rising stars the way China and India are now. And it was a non-state actor (a student who managed to kill an archduke) who precipitated the crisis that brought that whole society of states to its ruin.

The alternative devised as an alleged improvement, the League of Nations, lasted barely 20 years, from 1919 to 1939 (the Twenty Years Crisis, as E.H. Carr called it1), and ended in the worst hegemonial war in history. So, in comparison, the Concert of Powers clearly showed greater durability, and thus looks more hopeful as a possible model for solving future problems of crisis management and the preservation of peace, in what is again a multipolar world: one in which crisis may all too frequently be engendered, in the near future, by the consequences of climate change, if those changes prove as disastrous as has been forecast.

Both the League of Nations and (later) the United Nations did incorporate in their respective structures some element of the concept of a concert of powers; the UN Security Council is its present form. But it never worked to much effect in the 20th century because the necessary degree of diplomatic consensus between the powers was seldom present; and Security Council membership is now, of course, hopelessly anachronistic, still representing the power-balance of 1945.

The reason why I believe that current diplomatic mechanisms, despite their obvious limitations, may perhaps work better in the foreseeable years of the 21st century is that there now exist very powerful threats that affect the vital interests of all six of the great powers, though to differing degrees. What is even more important is that all of those threats come from outside the magic circle of the great powers themselves. That is a very unusual state of affairs. Usually the only threats great powers have to worry about come from another great power, or an alliance of them. In time, the membership of the Security Council ought to be amended, but even that is not a major priority. The great powers can and do always get together in less formal ways when they want to. In the global economic crisis of late 2008, the informal diplomatic and economic groupings of the G7, G8 and the G20 showed clearly their greater flexibility than the formal legal groupings of the UN.

The main threats the G20 powers all face are familiar: first, economic disaster; second, climate change; third, the jihadists; and fourth, the possible proliferation of nuclear weapons to smaller powers and even non-state actors. There is no better diplomatic glue than a threat in common. Four such threats—all long-lasting and difficult to cope with—seem to me likely to provide a fairly solid basis for diplomatic consensus, enough of a basis so as to make a concert of powers possible. And such a development is compatible with the survival of the UN in more or less its present form. What are vital are the realities of the ongoing re-distribution of power, and the degree to which frictions and rivalries (which will remain inevitable) can be prevented from damaging the necessary degree of consensus between the governments involved.

The society of states has never been a democracy. Usually it has been an oligarchy—the rule of a few: sometimes only two (as in the Cold War period), but very rarely only one (as in the “unipolar moment”). A major point of difference between the old systems of states with which we are historically familiar—the brilliant little society of Greek city-states, and the equally brilliant society of states of Renaissance Italy—is that, by comparison, the members of the emerging society of states are so numerous and enormous, as well as being, as a group, culturally and normatively diverse. All the decision-makers of the 19th century system were not only European and Christian, but drawn from the top stratum of their respective societies—from the Czar on down to Lord Castlereagh and Lord Salisbury. So their norms were rather similar, though by no means identical. Britain and France were relatively liberal; the others relatively autocratic.

The greatly increased diversity factor in the emerging system seems to me to supply the answer to the fundamental question of how much order the society of states can hope for. The system would rest only on the fragile stuff of diplomatic consensus, nothing more solid. It would not imply any direct central authority, able to enforce its edicts. But I am afraid that is the only system which can emerge in such a diverse a society of states; so it needs to be effective enough to cope with the basic tasks of crisis management. The only part of the world in which the sacrifice of sovereignty needed for any stronger system would be contemplated is the European Union. Elsewhere, sovereignty is mostly so recently restored that it is fiercely cherished. So, ours will remain a disorderly world. The most attainable ambition would be to restrain the level of disorder below that which might precipitate disaster to the world as a whole.

But why, it may be asked, should we expect even the minimal level of diplomatic consensus to be maintained consistently enough to permit joint crisis management, when there are prospectively so many frictions between the United States and both Russia and China (along with other adversary pairs, such as India and Pakistan)?

The evidence for sustaining that hope lies in the fact that, in a period of even sharper frictions between the United States and the Soviet Union, the necessary level of consensus did develop. That period was the Cold War, 1946–89 and, though it lasted 43 years, there were no major direct hostilities and very few Americans died at Soviet hands or Russians at US hands. The whole of that 43-year history is a testimony to the way in which a set of conventions of crisis management, plus prudent and creative diplomacy, averted disaster in what had initially been a very unpromising context of profound distrust between the nuclear powers. If it could be done then, when the two dominant powers seemed to have no interests in common save the avoidance of war between themselves, it surely should be possible now, when the 20 or so major powers have not only that interest in common but the others mentioned earlier.

One of the chief advantages of a system of international governance built on balance of power or concert of powers principles (which are two sides of the same coin) is that it contains within itself what can be and should be a well-understood built-in strategy should one of the great powers begin behaving unacceptably. That strategy is the anti-hegemonial alliance. To illustrate its use in the favourite scenario of the “China hawks” in Washington, let us suppose that China has grown so strong towards the middle of this century (strategically as well as economically) that its governing regime is contemplating a bid for hegemony in Central or East Asia. Any signal of such an ambition should, and in my opinion would, be the trigger for the formation of an anti-hegemonial alliance between the United States, Japan, India, Russia and Vietnam, since all five nations would have their interests prejudiced by any Chinese move in that direction. Most of the smaller powers in the Pacific would probably go along with that coalition. What is more, that prospective diplomatic reaction could be clearly signalled to the ruling group in Beijing and should act as a very serious discouragement to any top decision-maker contemplating such a move. So the ambition would (with luck) be suppressed at birth, and peace would be maintained. Admittedly, that strategy has not always been applied early enough, but it did work, more or less, in the 19th century to prevent hegemonial war for 99 years.

For the potential remaining seven years of the Obama administration, most of the diplomatic and strategic crises will almost certainly originate in the turbulent arc that stretches from the borders of Turkey to the tribal societies of the Afghanistan-Pakistan frontier. Obama’s recognition of the importance of that fact was quite audible in Washington even before his Cairo speech of June 2009.

The speech was called “A New Beginning”, and the stress should always be on beginning. To translate its enormously ambitious hopes into actual achievements on the ground—especially the long-contested ground of the old Palestine Mandate—will have to be the central focus of his diplomacy and his strategic decisions for at least the first two years of this term. It will take a lot of work, and some of the necessary decisions may generate domestic enemies. That will affect the elections of 2010 and 2012. So the speech was notable as much for its political courage as for its eloquence. No previous president, not even Kennedy, would have ventured openly to acknowledge, to a world-wide Islamic audience, the role of the Central Intelligence Agency in engineering the 1953 coup against a highly symbolic Iranian nationalist leader, Dr Mohammad Mossadegh, especially as the chief engineer of that coup, Kermit Roosevelt, was the scion of a famous US political dynasty.

But to move on from the symbolism of that journey to the practical possibility of achieving at least some reduction in the level of bloodshed and tension in the arc of crisis as a whole, a new hope may be found in its diplomatic and strategic context. For the first time, the Israelis, the Arabs, the US and most members of the G20 have a problem in common: Iran.

The Israelis see Iran as the primary threat to their entire community. The Arabs dislike the prospect that the non-Arab tribes of Iran, mostly Persians, might become the hegemonial power of the Gulf. The Sunnis among them (85 per cent) do not like the thought that the Shia governments in Iran and Iraq are now entrenched close to the heart of the Muslim world. The nations that depend heavily on Gulf oil (including most of the G20, notably China, Japan and India) are uneasily conscious that together they could send prices sky high again, damaging the recovery from recession. The nuclear great powers, including Russia, do not want another small power to join their exclusive club, especially as it might provoke a nuclear arms race among the other small powers of the area. The other small nuclear power, North Korea, is not in the same league: China’s own national interest ensures that it will exert control in a real crisis.

The clearest indication of the change in context in which the problem of reconciling the security of Israel with the right of the Palestinians to a viable sovereignty of their own must be considered is the emergence of the “57-state solution” alongside the two-state solution. The 57 states are of course the Muslim societies as a whole, including the 22 Arab societies. It is symbolic that such a notion has been put forward by King Abdullah of Jordan. A previous King Abdullah of Jordan, the present monarch’s grandfather, was in power in 1948, in the small state then called Transjordan. If he had chosen to re-name his kingdom not Jordan but Palestine, the title of the original mandate, there would have been a sovereign state called Palestine ever since 1948, and a great deal of the history of the area since might have been different. Words, including names, can be deeds in diplomacy.

But to return to the role of the G20 as a diplomatic instrument that might help forward Obama’s ambitions for the arc of crisis as a whole, the group already includes three Islamic governments friendly to his hopes (Indonesia, Turkey and Saudi Arabia) and might with advantage recruit three Arab states (Egypt, Jordan and Syria) which could play vital parts in the deal. An offer of membership, or at least associate status, might be a judicious gesture, and some old-fashioned ideas such as demilitarisation have already been mentioned. They would need to be accompanied by multilateral guarantees. Those negotiations must be a matter for the able diplomats Obama has deployed to the region.

The most important of Obama’s assets in securing a deal may nevertheless be those of his own personal history and temperament. Before his advent, no one would seriously have envisaged a United States president whose middle name is Hussein, whose father and stepfather were both Muslims, and who has, in a Third World village in Kenya, a clan of half-brothers and sisters and cousins who also are Muslims.

There must still be a question as to whether there is enough decision-making steel within the velvet glove of Obama’s eloquence. Only time will tell, but at the moment, on evidence of his dealings with the regime in Pakistan, and with Prime Minister Netanyahu on the two-states issue, the answer seems to be probably.

If a new international great-power consensus, along the lines implied in this essay, should emerge in the next decade or so, it will not be announced with a fanfare, as the Covenant of the League, and the Charter of the UN were. Nor should it be. It will creep in quietly from backstage during the dramas of world politics. That is a necessity of diplomatic tact, because the original Concert of Powers was by no means an international blessing to all the societies within its context. The European great powers benefited, while the outsiders undoubtedly got a very raw deal. China and India were recognised as empires, but that did not protect them from predation. Many other societies were not even recognised as having sovereignty over their territories. Fortunately, the contemporary distribution of power and the current norms of the society of states make a repetition of that colonialist aspect of the 19th century impossible or at least very improbable. Moreover, the process of globalisation has made the benefits which were once believed to go with imperial possessions available at much lower cost. So the incentive for political control, as against economic influence, in vulnerable small sovereignties has almost vanished among the more powerful governments. Even the tiny sovereignties of the Pacific seem secure in their identities.

There is a certain sense of going forward to the past about some aspects of the emerging patch of history, which will worry many people. The economies of China and India were probably the largest in the world as late as 1840. According to Goldman Sachs’ BRICs projections, they may be so again as soon as 2040. We have moved into what Indian scholars have long been calling “the end of the Vasco da Gama era”. They equate the voyages of that great navigator, along with those of Ferdinand Magellan and Christopher Columbus, with the beginning of the ascendancy of the West. That era lasted 500 years (from the late 15th century to the late 20th century), so its passing is of great import. It implies the beginning of the de-Westernisation of the norms of the society of states. No one can yet know how far that process will go, or how soon it will be effective, but it is certain that the three great non-Western civilisations—China, India, and the Islamic world—will each demand its place at the top table in due course.

This essay began by asking how much impact Obama can make on the turbulent, multipolar, crisis-ridden, nuclear-armed world in which he must act during the (potential) next seven years—a much shorter span than is allowed to top decision-makers in other political systems. Despite that constitutional brevity of tenure, he has seemed so exactly suited to the necessities of this particular patch of history as to bring to mind that adage, “cometh the hour, cometh the man”, as with Franklin D. Roosevelt in 1932 or Winston Churchill in 1941. Beyond the immediate problems of the global economic crisis, and within the much longer prospect of the environmental crisis, there is the primary task of maintaining consensus between the contemporary movers and shakers of the world, conveniently assembled at the moment as the G20 plus. As to his vital role in that group, he has already said, in his inaugural address, splendidly relevant words: “Power alone cannot protect us, nor does it entitle us to do as we please…our power grows through its prudent use.” If Obama’s successors continue to bear those words in mind, US power will remain not only popular but legitimate.