"How many Jews live in the Soviet Union?" runs a current joke.
"About 3,500,000."
"And how many of them want to leave?"
"About 5,000,000."
Hyperbole aside, it is estimated that perhaps 300,000 Soviet Jews would leave the country if they couldnot to mention any number of non-Jewish Soviet citizens. Few get out, whatever their religion, but Moscow now grudgingly permits about 2,000 Jews to depart annually. Most emigrate to Israel: last week, for example, Physicist Boris Zuckerman, a leading Soviet authority on magnetic resonance, arrived in Jerusalem with his wife and two children. Like those who preceded him, however,...