E.g. he has written:
"Without taxes, there would be no liberty. Without taxes there would be no property. Without taxes, few of us would have any assets worth defending. [It is] a dim fiction that some people enjoy and exercise their rights without placing any burden whatsoever on the public… There is no liberty without dependency."
Sunstein has a deep-seated belief in the power of government to improve society. He would point to something like the Civil Rights movement, where Congress pushed racial equality down the throats of the states and banned private conduct that discriminated on the basis of race, as a archetypal example of how government can force society to overcome its own failings.
It's the total opposite of the anarchist/libertarian viewpoint, but it's a self-consistent view of the world that he holds in good faith.