why dont you quote the full statement in context, rather than a snippet out of context? in that case it would be clear to you that it is permissible to do the right thing (i.e. a bris mila in the soviet union) even if its against the secular law. my quoted point being that if the authorities will harshly punish someone for making a bris (or other good deed), he might be exempt from doing it if he might get caught.
