Yes, Jews were the backbone of the Communist movement in Russia.
Yes, Jew made up the vast majority of commissars and political murders for the Reds.
Yes, the slaughter of almost one million Ethnic Germans in the Polish wars of 1920-23 by the Jewish-led Reds was a large factor in the Jewish hatred in Germany.
1. they were not the backbone. A significant part of the back-bone, but not THE back-bone
2. They did not make the vast majority -- they did make the largest number though and above their % of the population
3. 1 million ethnic Germans slaughtered in the Polish wars? Really? i haven't read that -- but I may be wrong. Can you explain further?
The slaughter of the Polish Wars gets lost in the fog of history, but it played a huge role in the origins of WW2.
http://en.wikipedia.org/wiki/Polish-Soviet_War