Why are Democrats so concerned with who's the head of the Republican Party?

The thing is that the GOP is a party without a head. Such a party can say and do anything it wants and there is no figure/person that would be accountable for the party's actions. That is what you see in gorilla warfare not in a real battle, in real battles the combatants and their positions are well identified. This type of behavior is created to attack in a vicious manner with little repercussions for the party. It is cowardly behavior.