Moisés Naím / Financial Times

Never say never. Because of the economic crisis, habits that seemed unalterable are suddenly being altered. Americans are now saving more and consuming less. Financial institutions are no longer betting the house on risky investments they do not understand. Many wealthy oil-exporting countries are tightening their belts. Everywhere, change is in the air.

Everywhere, that is, except in the way humanity responds to its most menacing threats. You know the list: climate change, nuclear proliferation, terrorism, pandemics and trade protectionism. Not one can be solved, or even effectively contained, without more successful international collaboration. That is not happening.

Indeed, when was the last time you heard that a large number of countries agreed to a major international accord on a pressing issue? Not in more than a decade. The last successful multilateral trade agreement was in 1994, when 123 countries gathered to negotiate the creation of the World Trade Organisation and agreed on a new set of rules for international trade. Since then, all other attempts to reach a global trade deal have crashed. The same is true with multilateral efforts to curb nuclear proliferation; the last significant agreement was in 1995, when 185 countries agreed to extend an existing nonproliferation treaty. In the past 15 years, moreover, India, Pakistan and North Korea have demonstrated their certain status as nuclear powers. On the environment, the Kyoto Protocol, a global deal aimed at reducing greenhouse gas emissions, has been ratified by 184 countries since it was adopted in 1997, but the US, the world’s largest polluter, has not done so and many of the signatories have missed targets.

The most recent multilateral initiative endorsed by a large number of countries was in 2000, when 192 nations signed the United Nations Millennium Declaration, an ambitious set of eight goals including providing universal primary education by 2015. Although some progress has been made, the failure of rich countries to fully fund these efforts, execution problems and the downturn make meeting the deadline unlikely.

The pattern is clear. Since the early 1990s, the need for effective multicountry collaboration has soared, but at the same time multilateral talks have inevitably failed, deadlines have been missed and execution has stalled. These failures represent not only the perpetual lack of inter-national consensus, but also a flawed obsession with multilateralism as the panacea for all the world’s ills.

So what is to be done? To start, we should forget about trying to get the nearly 200 countries to agree. We need to abandon that fool’s errand in favour of a new approach: minilateralism. By this I mean a smarter, more targeted approach. We should bring to the table the smallest possible number of countries needed to have the largest possible impact on solving a particular problem. Think of this as minilateralism’s magic number.

The magic number, of course, will vary depending on the problem. Take trade, for example. The Group of Twenty leading nations accounts for 85 per cent of the world’s economy. The G20 members could reach a major trade deal among themselves and make it of even greater significance by allowing any other country to join. Presumably, many would. It is the same with climate change. There the magic number is about 20. The world’s 20 top polluters account for 75 per cent of the planet’s greenhouse gas emissions. The number for nuclear proliferation is 21. African poverty? About 12, including all the major donor countries and the sub-Saharan countries most in need. As for HIV/Aids, 19 countries account for nearly two thirds of the world’s Aids-related deaths.

Of course, countries not invited to the table will denounce this approach as undemocratic and exclusionary. But the magic number will break the untenable gridlock and agreements reached by the small number of countries that can provide the foundation for more inclusive deals. Minilateral deals should be open to any country willing to play by the rules agreed by the original group.

The defects of minilateralism pale in comparison with the stalemate that characterises 21st-century multilateralism. The minilateralism of magic numbers is not a magic solution but is a better bet than the multilateralism of wishful thinking.