For months these Wagner soldiers have been told that the top of the Russian army is corrupt and incompetent.  Now that they are being integrated into the Russian army, how are they going to feel about taking orders from the very people they have been told are corrupt and incompetent? 
I can see a lot of different scenarios.
What happens when they are ordered to the front and they feel like they are being sacrificed because it is just inconvenient to keep them around?  If entire Wagner units are kept together, we could see a rebellion at some point.

I'm just saying, integrating these units into the Russian army could lead to some rather unpredictable situations.

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