What does the speaker believe that he and his foe would have done in different circumstances in the poem, The Man He Killed?

Rather than the encounter resulting in death and the destruction of one of the two men, the speakers says, “We should have sat us down to wet / Right many a nipperkin” (3-4). Rather than enmity and destruction, the speaker imagines that a companionship akin to friendship would have sprung up between the two men sitting down to share a drink.