In the halls of politics and power, most economists are like wallpaper-- full of intricate details but ultimately decoration. Jeffrey Sachs, however, is a brand name. A player. There's Jeff with the Pope. There's Jeff with U.N. chief Kofi Annan. There's Jeff with his save-the-world sidekick, U2's Bono.
Sachs, 50, has been around the planet more times than a space station to promote the U.N.'s Millennium Development Goals, to raise annual aid to 0.7 percent of GNP of the donor countries (starting with an extra $70 billion per year as of 2006), in order to halve poverty by 2015. He's a...