R. Shemariah was one of many great talmidei hakhamim who were stuck behind the Iron Curtain, and even if not killed by the regime, lived out their days in what can only be described as a living hell. While it was bad for everyone in the Soviet Union, for those whose lives revolved around Torah it was even worse. In accordance with the Lubavitcher Rebbe’s wishes, the elder Medalie did not attempt to leave the Soviet Union. While other rebbes and great rabbis were fleeing the country, the Rebbe told his followers to stay, as it was their responsibility to bring Torah to the Jewish people, even in times and places of darkness. He told them that they should not only think about their own physical and spiritual well-being but that of the Jewish people as a whole.
The Rebbe only changed his position in 1930 "when Stalinist terror was unleashed against rabbis and religious functionaries. But by then the difficulties connected with leaving the USSR were formidable and large scale emigration was impossible." What this meant was that virtually all of the children and grandchildren of these hasidim ended up completely assimilating, and I think that in retrospect we can say that it was a terrible misjudgment. However, it must also be stated that when communism fell, there were still Habad families that had remained religious throughout all this time. The next time someone complains about how Habad is now dominating religious life in the former Soviet Union, he should remember this.
This reluctance towards leaving the galut, even to go to Israel, is tied in with the Habad ideology that stresses the need to keep Judaism alive throughout the world. While this is generally a very good thing, as all world travelers can attest, sometimes the way it is expressed can be maddening for a religious Zionist to read.
There’s no substitute for being right. You can’t let your rabbis do all your thinking for you. For those who followed Rabbi Schneerson of Chabad and the Chofetz Chaim by staying in Europe, the consequences were deadly.