Democrats and Republicans both spend as much time demonizing their opponents as they do arguing the merits of their own position.
I saw an interesting show one time about tribal dynamics in a hospital. The nurses didn't want to be constrained by the rules on how much drugs particular patients should receive. They felt that the patient's comfort was the prime rule. The pharmacy department insisted on strict compliance with the rules. Both sides engaged in efforts to discredit the arguments of the other side, including resorting to demonizing the people in the "other" group.
"You're either with us or against us" goes on ALL the time. Considering it to be associated with traditional "tribes" misses the reality of the tribal dynamics going on all around us every day.
It just doesn’t work for me or anyone I chose to know, thank God. One of the reasons I quit working for the state after 8 years were those dynamics. I’ve never regretted it.