Author mean from the statement was that the government will not allow the press to make their opinions freely because they had a full control on the press and allow those statement which favors the government. Before the war, one group of media is in favor of south while the other is in favor of north so both groups support their respective states but after the war, the media who support the south will not be allowed to speak freely against the government of north due to their control over the whole country. So that's why the author made that statement.
