There has been a tacit agreement between the D's and R's for at least a century: "We get to govern 50% of the time and you get to govern 50% of the time. If we open the process up to other parties, both of us will govern less than 50% of the time."
That agreement seems to be leaking. I think both sides want to govern 100% of the time--and are willing to abandon democracy to get that.
Time for a new way with zero political parties and their strange deals: