In Animal Farm, why does Squealer support Napoleon?

Squealer supports Napoleon because he recognizes and loves
power.  Squealer and Napoleon have their own mutual admiration society.  It exists
because Napoleon makes rules and laws that benefit the pigs and Squealer, being a pig,
has no problem reaping the rewards.  Squealer carefully and shrewdly recognizes that
Napoleon is more concerned with power and control than Snowball is.  Within this,
Squealer casts his lot with Napoleon, as he recognizes that between a power challenge
between the two pigs, Napoleon will win.  At the same time, Napoleon is more predisposed
to making Squealer of use than Snowball.  Napoleon was not one for speeches and did not
revel in talking to the animals.  He was much happier being behind the scenes and
remaining in control with absolute power.  Napoleon was able to use Squealer to talk to
the animals and spread the message of his infallibility to them.  Napoleon cancels
Sunday meetings, stays inside the house, and stands on the pedestal when he does have to
speak.  He leaves this job to Squealer.  This is in contrast to Snowball.  His
impassioned speech about the windmill, as well as his ability to rally the troops when
under attack, and his preaching of Animalism to the animals makes Squealer useless. 
Snowball loved talking revolution to the other animals, and loved the idea of
communicating his ideas on delegation of work or building elements to enhance the power
of Animal Farm.  Squealer understands that Snowball does not need him.  He also
understands that Napoleon does.  For this reason, one rooted in self- interest and self-
advancement, Squealer supports Napoleon.