In Animal Farm, how does Snowball's scapegoat status benefit Napoleon and the pigs?

Makinginto a scapegoat is very handy forand the pigs because from then on, every time
something goes wrong on the farm they can blame it on him. It doesn't even matter that
Snowball's no longer around;can make up some ridiculous story about Snowball sneaking back to
the farm at night and committing acts of sabotage like wrecking the windmill.

So long as Snowball's still alive, Napoleon's determined to place him at the center of
a gigantic counter-revolutionary conspiracy in which the banished pig is working in cahoots with
Mr. Jones to overthrow the Animalist regime and restore human control to the farm. It's all a
total lie, of course, but it's a very...