You can’t have diplomacy with a group who systematically rapes and murders entire families.
You can’t have diplomacy with a group who purposefully targets civilians with reckless abandon instead of legitimate military targets to kill the people.
You can’t have diplomacy with a group who doesn’t believe you exist or should exist. That it would be better to execute you than negotiate with you.
You cannot have diplomacy with a group who brought mobile crematories to disappear your citizens. Who had lists for who should be be killed.
You cannot have diplomacy with a group who does not want diplomacy.
Early in WW2 the Jews would stand in line for hours to wait and be shot. They would queue politely to be executed. That is what “diplomacy” looks like in this case.
Ukraine was on the verge of surrendering early in the war. Then news of the Bucha atrocities reached the Ukrainian Leadership and they refused to surrender. Because surrender means certain death. That’s the thing folks don’t seem to get.. if you’re fate is to die.. or to fight and have a chance at not dying.
You fight.