This is just a helpful reminder because i haven’t read the book yet but here’s how you can tell what perspective (POV) it is:
(1st perspective uses: We, us, our,and ourselves are all first-person pronouns. Specifically, they are plural first-person pronouns. Singular first-person pronouns include I, me, my, mine and myself.)
&
(2nd perspective uses: you (singular and plural personal pronoun) yours (singular and plural possessive pronoun) yourself and yourselves (singular and plural reflexive/intensive pronouns))
There were a couple of reasons for this. First, the Americans were an invading force, and the Vietnamese were fighting on their own soil. Second, the Americans were not willing to make an all-out commitment to win.