The people had not decided on secession. The people refers to the whole people, the same people guaranteed the right to bear arms. A small section decided to accept the strategy of pretending to secession as a ploy to aid their insurrection. That small section began a war as a ploy to get others to join their insurrection.
Their insurrection failed. The victorious union reestablished their power and extended mercy to the deluded traitors.