Without Jewish emigration from the Soviet Union, the world would be a very different place. For one thing, this blog wouldn't exist. Here's a very interesting article on Soviet Jewish emigration in the early 1970s, when it became a mass movement. Among other things, the stereotype of the typical emigre as a well-educated Muscovite or Leningradnik is wrong; few of the early emigrants had advanced degrees, and they disproportionately came from the fringes of the USSR, where Soviet repression was both less consistent and more recent.