We live in unbalanced times – some would say to the point of unsane. Even those who avoid, or at least minimize, exposure to electronic media are powerfully effected by the currents in which we all swim together.
In political and social arenas, correct “posture” means having (or protraying) the right attitude. As individual humans it means upright on our skeletons (whether seated or standing), supported by our centers and balanced in our perspectives.
Persuasion and/or convincing will seldom produce this result.