Mr. Obama's administration was the amplitude of the left. It took the bob 30-years or so to get there. As the bob moves right in theory it should take 30-years or so to reach the rights amplitude; 15-years or so to the equilibrium. Now that is of course the pendulum operates in a vacuum.
I suspect the pendulum we are dealing with now is not operating in a vacuum. The window is open and storm clouds are forming consequently, the pendulum will not act as normal.
When the Democrats Russian Hoax 2.0 fails, there will be a 3.0 soon to follow. Speaking about today, the Dem's know that if the election were held today, no matter who ran against trump, he would win.
As we approach November 2020, the fervor will only escalate. At some point if the Dem's do not dethrone Trump all hell will break out.