The answer you are looking for can be found in Chapter 14 of this great novel, which details the progress of the creation of the first Israeli state and the huge variety of reactions that there are to this policy. Reuven, as somebody who supports this move, finds himself in opposition with a number of different groups of Jews who do not, most prominently Reb Saunder's followers. Although he is very angry, Reuven manages to suppress his emotions and maintain a stoical silence, which he is very glad for as the next few weeks show how the situation is developing:
For as the Arab forces began to attack the Jewish communities of Palestine, as an Arab mob surged through Princess Mary Avenue in Jerusalem, wrecking and gutting shops and leaving the old Jewish commercial centre looted and burned, and as teh toll of Jewish dead increased daily, Reb Saunders' league grew strangely silent. The faces of the anti-Zionist Hasidic students in the school became tense and pained, and all anti-Zionist talk ceased.
The events that transpired showed that Reuven was write to keep silent and let what happens do the talking for him, for the continued violence depicted in this quote argued far more eloquently for the need of the creation of a Jewish state than Reuven himself could have argued.