foot soldier vs helper

foot soldier and helper both are nouns.

Word	Noun	Adjective	Verb	Adverb
foot soldier	Yes	No	No	No
helper	Yes	No	No	No

As nouns, helper is a hypernym of foot soldier; that is, helper is a word with a broader meaning than foot soldier:

foot soldier: an assistant subject to the authority or control of another
helper: a person who contributes to the fulfillment of a need or furtherance of an effort or purpose

Other hypernyms of foot soldier include assistant, help, supporter.

foot soldier (noun)	helper (noun)
fights on foot with small arms	a person who helps people or institutions (especially with financial help)
an assistant subject to the authority or control of another	a person who contributes to the fulfillment of a need or furtherance of an effort or purpose