self-government vs liberty

self-government and liberty both are nouns.

Word	Noun	Adjective	Verb	Adverb
self-government	Yes	No	No	No
liberty	Yes	No	No	No

As nouns, liberty is a hypernym of self-government; that is, liberty is a word with a broader meaning than self-government:

self-government: government of a political unit by its own people
liberty: immunity from arbitrary exercise of authority: political independence

Other hypernyms of self-government include autonomy.

self-government (noun)	liberty (noun)
government of a political unit by its own people	an act of undue intimacy
	immunity from arbitrary exercise of authority: political independence
	freedom of choice
	personal freedom from servitude or confinement or oppression
	leave granted to a sailor or naval officer