It was an immensely appealing experiment, both in its idealism and in its simplicity: Let young Israeli and Arab musicians play together in an orchestra to show that communication and cooperation were possible between peoples who had long fought each other. [...] By the end of the workshop Israelis, Palestinians, Syrians, Lebanese and Egyptians had learned to play together and live together, and the West-Eastern Divan Orchestra was born. (It took its name from a collection of poems by Goethe, inspired by the 14th-century Persian poet Hafiz.) Since then, the orchestra has studied and toured under Mr. Barenboim's guidance and baton every summer.