ST. PETERSBURG (AP).- An exhibit opened in Russia on Thursday on the life of an American veteran believed to be one the few soldiers to fight for both the U.S. and the Soviet Union in World War II. The Russian Museum exhibit, titled “Joseph R. Beyrle — A Hero of Two Nations,” presents 260 artifacts from Beyrle’s life and military career, including a collection of his medals, uniform and photographs. His son, U.S. ambassador to Russia John Beyrle, attended the exhibit opening and said that though his father was called a hero by both nations he never considered himself one. “He always used to say that real heroes were those who never came back from the war,” Beyrle said in fluent Russian. Beyrle said his father “all his life was extremely grateful to the Russians, who saved him.” He said his father’s experience was a symbol of the strong relationship between the two countries. The ambassador said Russian soldiers were grateful for billions’ worth of Allied military aid sent t