Pierre Hassner, "Raymond Aron on the Use of Force and Legitimacy," Washington, D.C.: Brookings Institution Center on the United States and Europe, 2005.

Excerpt:

Raymond Aron, beyond his rich theories and deep analyses, remains for me above all a professor of moral and intellectual sanity. He was a teacher of what he saw as the 2 supreme intellectual principles: the respect for facts and the respect for the arguments of others. From his devotion to these 2 principles, Aron  achieved in his work a remarkable mixture of firmness and moderation, and awareness of the complexities of the world together with an understanding of the need for action and for choice.

Of course, Aron did waver on some issues. On the issue of the French nuclear deterrent and on the prospects for European integration, he changed his emphasis several times. But on most issues, he made a number of basic choices that are still relevant today. He broke with his left-wing intellectual friends over the fights against totalitarian communism. At the same time, he broke with his friends on the right over the war in Algeria and the Suez crisis. These positions and others left Aron quite isolated in French intellectual circles, but he never faltered in his convictions.

Online:
Brookings [pdf]