Question

What does he has affected to render the military independent of and superior to the civil power?

Answer 1

It means that the military works for the king and not for the people that it should protect. He refers to the King of Britain and the sentence means that he basically uses the army not to protect the people, but as his own personal army to fight wars against who he thinks is the enemy. Instead of military working to protect the people, the military does not have accountability with the people.