Some of our friendships are not based merely on political affiliation. This is not a shot, but please understand that not everyone is automatically looking for a clan and an enemy to bond over ( even though it is not uncommon and perfectly rational thing to do based on our evolutionary path alone ).

Not to search very far, me and my coworkers discuss politics ( and we do have somewhat divergent views ). The bubble only exists if one does not talk with other people. In other words, other people being like-minded is not an automatic pre-requisite.