That’s certainly a huge root cause, but it’s still in Congress’s power. The thing is even if all three branches are single party with slavish loyalty, they are letting the president usurp their authority. Even when they generally agree, where is the self-interest to protect the power they fought so hard to get? They will wake up one day with nothing

Congress also is letting the face eating leopard roam free in their territory. They believe only peons will get their faces eaten, but when that leopard is tired of peasant meat, it will find Congress faces mighty tasty.