Americans celebrate Columbus Day Monday to commemorate what is known as the discovery of the "New World" by Italian explorer Christopher Columbus. As Italian Americans mark the holiday, New York's Italian American Museum has opened an exhibit. The display explores a painful time when 600,000 Italians living in the United States were designated "enemy aliens" during World War II. After Japan attacked U.S. forces at Pearl Harbor on December 7, 1941, President Franklin Delano Roosevelt implemented what was called the "Alien Enemy Act." Unnaturalized immigrants, or aliens from Japan, Italy and Germany living in the United States, were to be...