You don't know how much national unity that event will grant to SU. You can balance it out and make it into a very difficult decision...
Ah yes, I was just trying to guess based on how much "national unity" it gave the Soviets historically: Even though Stalin was paranoid, he did have a reason for doing it, but in my limited historical knowledge the damage it did far outweighed the benefits (again, speaking historically). If they balance it out, it will probably be ahistorical, though I would support it.