Momentum has been building to make this the year when the world gets serious about changing the future for its poorest people, write Bill Gates and Bono
There are moments in history when civilisation redefines itself. Times when momentum builds to bring down a status quo which people are no longer willing to accept. The abolition of slavery was one. So was the fall of the Berlin Wall and the ending of apartheid.
When it comes to the wanton loss of lives to extreme poverty and disease, 2005 might be such a moment. Right now it seems unthinkable: the year has begun on an incomprehensibly tragic note in Asia. Yet momentum has been building to make this the year when the world finally gets serious about changing the future for its poorest people.
The coming 12 months are a test for us all - especially the leaders of the G-8 nations, whose vision and resolve have never been more on the line.
History's judgment will be harsh if we fail, precisely because we are the first generation which truly has the power to succeed. New tools and ideas are creating opportunities which were, until very recently, unthinkable. Conventional wisdom used to be that foreign aid could not buy measurable results. That attitude and its ally, indifference, is eroding in the face of dramatic progress, particularly in health.
Diseases which have wiped out generations of poor people are now themselves on the brink of extinction. Fifteen years ago, polio afflicted 350,000 people; today, that number is 800, and it could soon be zero. In the last five years, increased immunisation has saved the lives of half a million children - a number which could triple over the next decade.
Another abhorrent idea is also fading: the notion that poor countries, shackled by old Cold War debts to the richest countries, have to pay us back no matter what the cost in human suffering. Now that wealthy nations are writing off some of that debt, the poorest countries have been able to boost their spending on other urgent priorities, such as health and education.
Uganda, for example, has used its savings to double the number of children in primary schools.
More than ever, the world knows what works. Five years ago, world leaders vowed to make it work even better, in more places, for more people. A series of Millennium Development Goals pledged to the world's poor that in this new century basic human needs would finally be met. Food, clean water, health services and education would be the birthright of every child.
Heads of state are talking seriously not just about fighting disease and deprivation, but about ending it.
After a decade of declining aid flows, trends have been reversed, including in Ireland. This is a welcome shift from several years ago.
Still, the uncomfortable truth is that no country is doing enough - and some, like Ireland, are not increasing aid as fast as they promised.
The temptation to trim or cut back development aid is strong in the light of budget pressures. But this has to be weighed against the costs of inaction. In Africa today, 10 million AIDS orphans need care because their parents could not get access to anti-retroviral drugs.
There may be 20 million more by 2010. Surely it is cheaper, smarter and easier to prevent fires like these from starting, than to stop them once they are raging.
Only one of us is known for crunching numbers. But both of us believe that investments in human potential pay off many times over.
They have the power to end extreme poverty. But only if we learn to think big again. The Marshall Plan, which rebuilt Europe after the second World War and became a bulwark against Soviet expansion, cost the United States 2 per cent of its GDP over four years.
Today, in tense, nervous times, an investment of less could not only transform more people's lives, but also transform the way those people see us.
Our momentum, then, is real but fragile. This year brings a unique convergence of global summits, progress reports and negotiations on debt, trade and effective aid. The acronyms - G-8, UN MDGs, WTO, IMF - cause eyes to glaze over, but they amount to the best chance yet for the world to learn from its successes and keep moving forward.
For starters, we hope that the leaders of every developed nation will resolve to take four crucial steps in 2005. The wealthy world has already committed to some of these ideas - and promises made must be promises kept.
First: double the amount of effective foreign assistance, possibly through the International Finance Facility, a proposal to frontload aid and get it flowing immediately.
An initiative backed by the British and French using the same principles is ready to roll now and could save five million lives by increasing child immunisation.
Second: finish the job on the debts of poor countries. They need more than relief - they need full debt cancellation.
Third: change unfair trade rules, thereby creating a pathway for poor countries to reach self-reliance.
Fourth: provide funding for the Global HIV Vaccine Enterprise, a more aggressive and co-ordinated approach to developing a vaccine.
In these and other ways, our governments can make history - but only if we demand that they do. That is why, three days into the year 2005, movements have already taken root, bringing unlikely allies - CEOs and NGOs, pop stars and priests, mothers' unions and student unions - together in a global campaign for justice.
The story of 2005 will have its leaders and laggards, and in a year's time it will be clear to all of us who was who. In the meantime, it is up to us how we want our generation to be remembered. For the Internet? Or for the "war on terror"?
Or for finally deciding that where a child happens to live will no longer determine whether that child gets to go on living?
Lines of latitude and longitude are stronger than any Iron Curtain and divide us more than apartheid.
The world has the resources and the technology to change all this. The question to be answered in 2005 is whether we can summon the will.
Bill Gates is co-founder of the Bill & Melinda Gates Foundation; Bono is lead singer of U2 and co-founder of DATA (Debt, AIDS, Trade, Africa)