By Martin Wolf

Human beings must co-operate intensely with strangers. They are also intensely suspicious of those different from themselves. The reconciliation between these two aspects of ourselves is the greatest challenge of our age.Consider the following characteristics of our world: technology has reduced the costs of transport and communications to an unprecedentedly low level; the world economy has become more integrated than ever before; ideas can be disseminated with ease; we live within some 200 states with vastly different capacities; huge gaps have emerged between average living standards in the poorest and richest countries; economic failure and success generate huge social pressures in poorer countries; powerful incentives attract people to migrate from poor to richer countries; and, finally, values, beliefs and identities remain hugely diverse. In short, we live cheek by jowl, but are deeply divided. Moreover, historical methods of managing conflicts among strangers are also now unworkable.

The experience of the US in Iraq demonstrates, for example, that empires do not work. Without some legitimacy, only a ruthless despotism can retain an empire. The US lacks the legitimacy and, happily, the ruthlessness. As inconceivable as a world empire is a universal religion. Today’s world possesses a hodge podge of faiths and non-faiths. States now rest on single religions (as in Iran or Saudi Arabia), civic creeds (as in the US), national identities (as in Japan), procedural values (as in Switzerland) or on no shared identity (as in much of sub-Saharan Africa).

Our world is one of interdependence. In the absence of co-operation, we have the capacity to impoverish ourselves, if not destroy ourselves altogether. But our world is also one of hostility. Those hostilities are, moreover, not only between states, but within them as well.
As Robert Leiken notes in the latest Foreign Affairs, “Europe now plays host to often disconsolate Muslim offspring, who are its citizens in name, but not culturally or socially.”

Yet that is just a small part of what is happening in our world. Nationalism is also on the rise. China and Japan are, for example, increasingly economically interdependent and politically estranged, just as happened with the great European powers prior to 1914. Comparable tensions can be seen emerging in the relationship between China and the US. In these cases, too, the tribalism shows itself in cycles of grievance and suspicion.

It is far easier to enumerate the challenges than find the solutions. But a tough-minded liberalism, in its European more than American sense, is the only answer. That was the solution proposed by the founders of the multilateral world order after the second world war. It remains the best solution today. We must agree, within reason, to differ. In essence, this means that we agree more on procedural norms than on substantive ones. Moreover, we enshrine those procedural norms within institutions.

This means multilateralism. The only alternatives are empires or the balance of power. Neither is a workable basis for international order in so interdependent and dangerous a world. The former is impossible at the global level. The latter is inherently unstable. International order can only be built on co-operation among the larger powers within a system of principles and rules that all share in making and to which all are committed. The attachment of the Bush administration to unilateralism is a huge strategic blunder. It leaves the US shorn of legitimacy, bereft of allies and desperately trying to impose order by force. This strategy is failing, as it was bound to do.

This also means addressing grievances. How countries deal with supposedly internal matters, such as the Chechen conflict, are matters of global concern, because they have global consequences. The same, self-evidently, is true of relations between Israelis and Palestinians or India and Pakistan.
Again, this means helping states to work better and promoting development within them. We cannot live safely in a world in which non-state actors operate freely with access to lethal technologies. We need to ensure that all states are able to control their territory. This is why it is right to intervene powerfully where states collapse and to promote economic development, which is not only good in itself, but provides the foundation of greater political stability in the long run.
This means, above all, finding a modus vivendi between different beliefs and values in the world as a whole and within countries.

 
At the global level this is easier than within countries, since the demands of tolerance and co-operation are so much greater when people live side by side. Multiculturalism always has limits. But the limits are particularly obvious within a state if one group believes legitimacy derives from voting and the other that it derives from a holy book. The aim is to develop institutions that generate the trust needed to live in peace. Claims that one possesses the faith that provides an answer to everything, while all alternatives are worthless, are inconsistent with such trust and co-operation. So are calls to holy war. Yet so must be imposition of democracy by force.

We have come to a new stage in the history of our species. We live in what is becoming a globalised world while remaining divided in countless ways. Our ingenuity has created the integrated world, just as our history have created the divisions. We must find ways to live side-by-side, in peace and co-operation, despite our mutual distrust and dislike.
We need enough trust to be able to co-operate, as Paul Seabright of the University of Toulouse argued in a brilliant book published last year. This can only come from the liberal values of toleration. Liberalism is the only unifying creed for a divided world. Can it win against those who despise tolerance? The omens look dire. But if it fails to do so, we will share a miserable world.