I.e., for the happiness of the People. In the socialist context of the scene this line has a Marxist overtone, suggesting the People's eventual triumph after a period of skulking deception and revolt. Note that Nostromo immediately barricades the house, symbolizing united society shielding a secret.

The barricaded house, of course, also mirrors Nostromo's first scene in Chapter 1-4, but with a reversal: there, he was barricaded out, while here he is barricaded in.