Katie Pavlich asks at Townhall.com whether Joe Biden’s supporters will allow him to follow through on a key promise from his victory speech.

Speaking from Wilmington, Delaware Saturday night, former Vice President Joe Biden promised to “unite the country” as president and claimed he has a “mandate to march on the course of decency.”

But will the leftists in Biden’s Democrat Party allow him to do so? After all, the newest members want to keep track of Trump supporters so they can be punished, list Trump administration staffers so they can remain unemployed and members of the media want to “burn down” the Republican Party with “no survivors.”

It’s up to Biden to live up to his promise of “decency” and unity. He’ll have to hold off the left in order to do it.

Speaking of holding off the left, that’s the only way for Biden to avoid proposing disastrous public policies as well.

A recent study by a group of highly regarded economists at the Hoover Institution, including two former members of the Council of Economic Advisers, found that the full panoply of Biden’s policy proposals — Medicare for All, big tax hikes on the wealthy and the working poor, the massively expensive Green New Deal, and thousands of impending regulations — would have devastating consequences for the U.S. economy.

Why? Not only would they destroy the economy’s current renewed momentum, but they would require enormous tax increases on all Americans, businesses and individuals alike. It would hit the U.S. economy with its largest tax shock ever, and take it down.

The size is beyond dispute. As President Donald Trump would say, the coming tax-hike tsunami from Bidenomics would by “Yuuuge.”

According to the nonpartisan Committee for a Responsible Federal Budget, Biden’s projected tax increases total $4.3 trillion over the next decade, and that’s a conservative estimate. Trump, meanwhile, would cut taxes by about $1.7 trillion. The quick math: That’s a $6 trillion difference.