A reader who prefers to remain anonymous emailed a very smart observation:

Like going from 0 - 90 in 60 seconds.... Democrats have gone from Left to Far Left in about a minute. They've slid down that slippery slope so quickly that people wonder how fast Democrats will go for what is farther down the slope than socialism.

Bingo!

It's as if a mask has been torn away.  Probably out of frustration over President Trump's tremendous success in ending the "new normal" that Barack Obama foisted upon us, a shrinking labor force participation rate, one-percent-a-year economic growth — basically matching populations growth, which means stagnation — and growing dependence on government handouts because job opportunities are simply not there.

My reading is that moderate Democrats have been intimidated by Trump Derangement Syndrome into opposing everything that President Trump has done, even those things that help their constituents.  It takes a person who is very secure — for example, billionaire Robert Johnson, the founder of BET — to stand up to the TDS bullies.

By defaulting, the radicals have been handed power within the Democrats' congressional caucuses and the media wing of the party.  They are so full of their own momentum that the normal practical restraints on radicalism have slipped away.

History of the last century is full of examples of radicals taking control and moving revolutionary movements toward tyranny.  The French and Russian Revolutions ended badly for the moderates and for the rest of society.

Will the remaining sensible Democrats wake up?  I am not optimistic.  The only thing that will save them, and possibly the Republic, is utter, overwhelming rejection at the polls in 2020, handing both houses of Congress to the GOP and re-electing President Trump, who can then implement institutional reforms to root out the Deep-Staters and actually redirect the federal government back to its constitutional limits.