Former U.N. diplomat Giandomenico Picco has died at the age of 75. Picco, whose negotiating skills helped resolve some of the thorniest crises of the 1980s and 1990s, died on Sunday after a long illness, his son, Giacomo Picco, said. The elder Picco helped negotiate an end to the Iran-Iraq war and the freedom of kidnapped Westerners by Hezbollah in Lebanon. Picco also helped facilitate the 1989 withdrawal of Soviet forces from Afghanistan. His understanding of Iran allowed him to negotiate the release of hostages kidnapped by groups with ties to the Islamic Republic, including Terry Anderson, the bureau chief in Beirut for The Associated Press, who was held the longest — from 1985 to 1991.