There was no leader. There was no way of communicating or fighting back. The Germans had overpowered them. The Jews didn't constitute a country with a government. The Jews were also a very diverse group of people. On the one hand, there were very traditional Orthodox Jews in countries like Poland and Romania. On the other hand, in Germany, France and the Netherlands there were large groups of Reform Jews (as well as more traditional Jews). Many were also non-believers. Some were conservative, others were liberals and yet others were socialists (of all varieties). Many in Western and Central Europe had enthusiatically embraced emancipation and were keen bearers of modernity; others, mainly in Eastern Europe, were very traditional. Having said this, there was the designated 'national home' in Palestine, which was under British rule from 1917-1948. There the largest group of Jews was headed by Chaim Waizmann, but there was very little that he could do. Moreover, he had no authority to speak for the Jews in general.