If we fight them and they fight us, and we kill them and they kill us, who will be left of the Muslims?
Muawiyah said this after Ali RA's assassination, as his camp in Syria and Hasan RA's supporters in Madinah stood on the brink of war, before sending word proposing reconciliation.
Do you really want to go on to the death and let Allah decide? Or for the sake of the ummah, let us give up the khilafa with some conditions.