Republicans in Congress used to extol the virtues of “divided government,” when they controlled Capitol Hill while a Democrat and his family were residing down the street in the White House.

Guess what. Divided government is about to be tossed into the crapper. On Jan. 20, a Republican — Donald J. Trump — will take the oath of office as the 45th president of the United States; meanwhile, the GOP will retain control of Congress, although with slightly diminished majorities.

But we’re going to have one party in charge of everything.

Oh, boy!

The last time one party ran the whole show was from 2009 to 2011. Democrats were the big dog. What did they do when they ran the government? Oh, the 111th Congress — along with the president — managed to save the nation from total economic collapse, despite many Republicans’ best efforts to stop them.

Then the GOP took over both congressional chambers and began obstructing just about everything the Democratic president, Barack Obama, sought to do.

What lies in store for the new GOP president and his fellow Republicans who run Congress? That might depend on how well Democrats learned the obstructionist practices of their “friends on the other side of the aisle.”

Trump intends to do a few things that are anathema to Democrats. He wants to repeal environmental protection laws; he wants to toss aside the Affordable Care Act — although he now says he hopes to save the strongest portions of it; he intends to “build a wall” across our southern border; he hopes to ban Muslims from entering the United States of America.

I believe Trump once also said he intends to make department store owners force their employees to wish their customers a “Merry Christmas” during the holidays. Government overreach? Uh, yeah!

In each of these cases, I am all for a little obstruction. I trust Democrats have learned their lessons well from their Republican colleagues.