Diplomacy is when you make offers to different factions to determine if you’re at war, peace, or alliance. Factions will have a relationship, if it goes to 0, that means that they are at war. The next log will be about bribing.
The infdev screenshot is from turn 77, where a Benderian diplomat is trying to make an offer to a Dremuxian. Sometimes, the bribe button is gone, and another button, ceasefire, is still on the works.
