I think we see things differently there. Sure when we had Republicans presidents for the most part the movement left slowed to a crawl. But the question is how far left does one want to go. I have no problem moving left in a slow steady manner. But I don't want leaps and bounds. I don't think the American People wants gigantic leaps either. Not as a whole.
We seen what happened when Obama went full fledged ACA in 2009/10. The American people weren't ready for it and that resulted in a 63 seat loss. Bill Clinton did the same thing in 1993/94 which resulted in a 54 seat loss. The Republicans gained control of the house for the first time in 40 years.
There's a comfort zone to most people. It okay to push that comfort zone to the edges, but don't go over. If you want a giant leap, you have to make sure the people are behind that leap. I think one has to be a realist when it comes to politics. One needs to realize what is possible and what isn't. What will cause a giant blow back and what won't. Numbers can be very useful here.
Sometimes it takes years to bring the people to accept a major change in governance or in their lives. The trick is to know when the people are ready. JFK realized this with Medicare, it went no where and he didn't push it. LBJ got it passed with bipartisan support. Compare that to the ACA which was a one party affair. LBJ went on with civil rights, voting rights and more. The time was ripe during LBJ, not so during JFK.
If we get a Democratic president this November, I'd advise him to be very aware of how much the people are ready for. Push the edge of change to the edges of their comfort zone, but don't go over. Sometimes it takes time to win over the people. Push beyond their comfort zone, I'll guarantee the Democrats will lose the house in 2022. Learn from history, become a realist as to what can and can't be done.
Politics is the art of the possible. The good politician knows this, grabs the possible and put the impossible off until another day. If not, all progress stops dead cold when the other party regains control of congress because of an overstep at the time.
It's high past time that we start electing Americans to congress and the presidency who put America first instead of their political party. For way too long we have been electing Republicans and Democrats who happen to be Americans instead of Americans who happen to be Republicans and Democrats.