divisive - Causing disagreement or hostility between people, tending to disrupt unity or harmony.
The election was fought over the deeply divisive issue of immigration, and people on either side of the issue can't see things from the other point of view.
tremor - A slight shaking movement, such as one caused by an earthquake or instability; also a subtle or faint sign of emotion, such as fear or excitement in the voice or body.
Because he was nervous, his voice had a significant tremor during the presentation.