Sgt. Jeannette Winters became the first American woman to die in the U.S. War against Terrorism yesterday when a U.S. military plane crashed into mountain in southwestern Pakistan. The plane was carrying Winters, 25, a radio operator, along with six other Marines. Winters, an African-American, joined the Marines in 1997, and like the other service members on the flight to Shamsi, Pakistan, she was based at the Marine Corps Air Station in Miramar, California. The cause of the crash is being investigated, but military spokespeople believe it to be an accident.