France won key battles by torturing suspects for intelligence. But the bigger lesson is that it lost the war. The fact that French military leaders resorted to the extensive use of torture shows that they had lost the support of the populace at large. It is a lesson that seems to have been ignored by American leaders as they prosecute a war in Iraq.
The French use of torture in Algeria didn't happen overnight. It was a reaction to a deepening crisis in which the French military, originally looking for suspect Algerians, came to see all Algerians as suspects. A signatory to the Geneva Conventions on war, the French government nonetheless insisted that these conventions weren't applicable to the Algerian situation. Its rejection of Geneva protections, and the consequent acceptance of harsher methods of interrogation of prisoners, proved to be fertile breeding ground for torturers.
Since late 2001, because the attacks against al-Qaida and the Taliban in Afghanistan, the U.S. government has, like the French in Algeria, displayed a clear ambivalence toward the Geneva Conventions. At times it has professed adherence; at others, it has scoffed. Even the reasoning for rejecting these conventions is identical to earlier French arguments: like the United States today, the French military argued that countering terror required harsh methods.
In Algeria, concerned about countering a 'revolutionary war,' French generals increasingly seized authority from civilian leaders. They ran roughshod over legal protections for the population. The main opposition to French rule, the Algerian National Liberation Front (FLN), seized the initiative. But the FLN was not simply the virtuous revolutionary force beloved of the left; like many weak revolutionary forces (for example, the Vietnamese Viet Minh at the beginning of its war against the French), it too resorted to terror to achieve its aims.
It's probably trite to say also that the French in Algeria insited that their interrogation methods did not amount to torture because of fine distinctions advanced by the French military. The difference in the US case is that it is the civilian leaders in the White House and the Pentagon who are advocating fine distinctions to exclude themselves from the Geneva Convention and the Torture Convention.