9/11 was a crime against the United States and a crime against humanity. Treating the criminals who perpetrated it as soldiers at war with the United States and the West only elevated their status and standing and began the “War on Terror.” The war was as ill formulated as it was executed. The result: Kabul is an island protected by NATO, with much of the rest of Afghanistan in the hands of warlords and the Taliban, and Iraq has been turned from an authoritarian state into a failed state, fragmented into regions. The cost in lives has been horrendous. Hundreds of thousands have died, and millions have been displaced.

What the War on Terror has disclosed is that the world’s mightiest power cannot conquer and pacify even relatively weak and divided countries. Initial victory proves illusory in the face of hostility to the victors and contested ideologies. The bombast of the United States and the West has been disclosed. The rhetoric of the “coalition of the willing” to bring democracy and peace to Afghanistan and Iraq has been shattered by the reality of car bombs and anti-personnel landmines. The killing goes on. As the “American Century” has dissolved in a decade, it has become clear that the wars in Afghanistan and Iraq symbolize the steady decline of Western power—that is, the ability of the United States and its allies to shape the world in their own image and according to their interests and rules.

After the dust settles, one finds a new multipolar world, with the center of economic gravity shifting to the East. The West no longer holds a premium on geopolitical or geoeconomic power. Different discourses, or concepts, of governance have become more commonplace and challenge the old Western orthodoxy that informed the postwar consensus. At the multilateral level, the emergence of gridlock marks many of the world’s most pressing international negotiations. Why? Decision-making has stalled in most of the key international decision-making fora, affecting climate change, trade rules, financial market reforms, and nuclear proliferation. The West can no longer write the rules as it once could. The emerging powers of the East and the South can veto the deals the West puts on the table even if they cannot yet write the new agenda.

The War on Terror has weakened the UN system, marginalized the Security Council in the face of great geopolitical tensions, and reasserted power politics at a time when such politics alone cannot resolve many of the central global challenges and risks we face living in a global age. Fighting “the other” misses a deep and more fundamental point—that on many of the most pressing issues of our time, “the other” is now our collective problems and collective threats. Reasserting our identities as Americans, British, French, Chinese or Christian, Jewish, Muslim, Hindu will not generate the means to address or resolve these issues.

Ten years on from 9/11, we see that the “end of ideology”—the much-heralded victory of democracy and markets—was as naive as it was misleading. Instead, we inhabit a much more complex mosaic of languages and discourses, of ideas and interests, and of identities and political associations. This is a much messier world than was understood by the architects of the American Century. It is a world that does not easily bow down to the destructive power of bombs and missiles. Consent and reconciliation cannot be carved out by armored vehicles and drones. The complexities of difference, culture, identity, and human associations can be changed only by creating spaces for voice and self-determination, spaces free of domination, whether this is the domination of conquering powers, fanatical religions, or authoritarian rulers.

This messier world is the terrain once again of politics, where politics matters just as much as ever. Yet unlike in previous eras, the nature of our politics needs to be worked out at many levels, from the local to the global. We live in an era where the fate and fortunes of countries are increasingly intertwined. I call this a world of “overlapping communities of fate.” Whether the focus is on economics, security, the movement of people, communications, or culture, there is now a global dimension to the forces, processes, and outcomes that bind human societies together. This creates both huge opportunities for development and prosperity and greater risks and challenges.

Throughout modern history, from the late sixteenth century to the present period, the business of politics and the decisions of public life largely unfolded within the borders of states, unless these were pierced by violence. States and governments, autocratic or democratic, made decisions within and for those in bounded territorial spaces. Yet today, most of the challenges we face are problems that spill over borders. Preoccupations with state interests or the welfare of particular people above all others cannot alone unlock the proper nature and form of politics in a global age. Or to put the point another way, state-first politics, realism, and hegemonic raison d’être are inadequate and insufficient ways of pursuing politics in dense webs of connections between peoples and communities. The alternative is a politics based on mutual recognition, the singular importance of each and every human being, and public decision-making that is transparent and accountable to all significantly affected by its impacts irrespective of borders. In sum, realism is dead, and cosmopolitanism maps the way ahead.

David Held is Graham Wallas Professor of Political Science at the London School of Economics, co-director of Polity Press, and general editor of Global Policy.‬