In profile: Union of Concerned Scientists turns 40

Science: On 4 March 1969, some of the most prominent scientists at the Massachusetts Institute of Technology (MIT) issued a declaration of political dissent and scientific self-criticism. Stirred into action by student protests against the war in Vietnam, the professors convened a campuswide meeting and declared that the "misuse of scientific and technical knowledge presents a major threat to the existence of mankind." The statement bore the name of a previously unknown organization: the Union of Concerned Scientists (UCS).

Forty years later, UCS has 80,000 members and a staff of 130 working in four cities. The organization campaigns to shrink nuclear arsenals, fight global warming, and reduce agriculture's harm to the environment. For 8 years, it was a thorn in the side of the Bush Administration, criticizing White House policies and zinging its appointees for "politicizing science." That aggressive approach raised its visibility and helped triple its budget this decade, to almost $20 million.

But just as some MIT faculty members of yesteryear ignored the teach-ins and went ahead with their normal duties, some scientists believe that UCS cannot claim to be the conscience of the scientific community. "Many of its statements and conclusions … were perverse oversimplifications of complex issues," says John Marburger III, science adviser to President George W. Bush and a frequent target of UCS attacks. "I think it's hard, maybe impossible, for an advocacy organization to be entirely science-based.