war vs struggle

war and struggle both are nouns.

Word	Noun	Adjective	Verb	Adverb
war	Yes	No	Yes	No
struggle	Yes	No	Yes	No

As nouns, struggle is a hypernym of war; that is, struggle is a word with a broader meaning than war:

Other hypernyms of war include battle, conflict.

As verbs, struggle is a hypernym of war; that is, struggle is a word with a broader meaning than war:

Other hypernyms of war include contend, fight.

war (noun)	struggle (noun)
the waging of armed conflict against an enemy	strenuous effort
a concerted campaign to end something that is injurious	an energetic attempt to achieve something
an active struggle between competing entities	an open clash between two opposing groups (or individuals)
a legal state created by a declaration of war and ended by official declaration during which the international rules of war apply

war (verb)	struggle (verb)
make or wage war	be engaged in a fight; carry on a fight
	to exert strenuous effort against opposition
	climb awkwardly, as if by scrambling
	make a strenuous or labored effort