It is impossible to win a war that you cannot define. That seems to be the main lesson to be drawn from Afghanistan, where a so-called victory seems ever more unreachable. It is also the conclusion of several experts on the region, who fear U.S. forces would be mired forever in that unjustly punished country.

Civilians can sometimes offer insights into a war situation that professional warriors cannot do. In 2001, American writer Philip Caputo offered a unique insight into the Afghan psychology. He had spent a month in Afghanistan with the mujaheddin as a reporter, during the Afghans' decadelong war with the Soviets.

At some point in the 1980s, he was accompanying a platoon of mujahedeen who were escorting 1,000 refugees into Pakistan. They had to cross a mountain torrent on a very primitive bridge, consisting essentially of two logs laid side by side. In front of him was a 10-year-old boy, separated from his family, his feet swollen from several days of barefoot marching.