Before his passing, the Mitteler Rebbe spoke a Chassidic discourse explaining why Jewish boys of 5 or 6 years of age were being drafted into the Russian army. He explained:

The nature of a person is that when not allowed to do something, he is aroused witha desire to do it. In this case, Jewish soldiers are being forcibly denied the opportunity to do any mitzvos. Therefore, their desire to do a mitzvah is aroused in a very powerful way.

Right now, since many Jews are doing mitzvos without feeling, this decree will cause them to yearn for mitzvos.

G-d forbid to say this was done to punish the Jewish people; rather, it was done to correct a problem. Whatever Hashem does is for the good and benefit of his people.

Quoted in The Mitteler Rebbe, A Biography, by R' Sholom D. Avtzon