In another diary entry, the Frierdiker Rebbe writes that his father wanted Russia to win, not Germany.
When he told the Rebbe Rashab that Germany is bigger and more powerful, he replied that the only way for Russia to win at least something is for the Czar himself to go to war and lead it.View it inside: רוסטוב על נהר דָ ן א' תצוה ב' אד"ר, ע"ו