We elected a Nomad who was familiar with our people and customs and explicitly was trying to understand us and how we govern.
A conquering nomad would do no such thing, and would rule however they pleased because they were strong and we were weak. They would try to attack all of our neighbors, and when we inevitably started to lose land, we would spiral into a failure cascade and fracture into a million pieces.
So, if bribe or tribute don't work, we'll have to fight to the death to avoid being ruled by a nomad who would ruin our civilization through a war of conquest. Damn.