Mexico's former Ambassador to the UN, Adolfo Aguilar Zinser, was killed in an auto accident Sunday. We first met Adolfo a decade ago at a private dinner in the northern Mexican city of Monterrey, when he was already working to help Mexico achieve democracy after decades of dictatorship. Adolfo was a man of keen intelligence who instinctively sensed his nation's hunger for freedom and worked to make that dream real, often despite the active opposition of the US government. He was a nationalist who loved his country.

After the miles he traveled and the things he achieved, the fact that Adolfo died behind the wheel of a car while near his home is tragic and pointless. And he is not the first member of Mexico's democratic movement to die in an apparently random car accident.

We remember in 1989, during the dark years under Carlos Salinas, when one of Mexico's great civic leaders, Manuel J. "Maquio" Clothier, died in a similar auto accident. Adolfo was one of the first members of the political opposition to go to the Clothier home and console the grieving family when many others were afraid to do so. As Maquio said, Aguilar lived: "A boss gives orders to men, a leader helps them find their own way."

The citizens of the Americas have suffered an enormous loss by the passing of a man who was not afraid to stand by principle, to defy the forces of institutional corruption which still control Mexico, and pay the price for doing so, an example which many American politicians should take to heart.

Descanse en paz.