President Biden recently held an undisclosed East Room session with historians that included discussion of how big is too big — and how fast is too fast — to jam through once-in-a-lifetime historic changes to America.

Why it matters ... The historians’ views were very much in sync with his own: It is time to go even bigger and faster than anyone expected. If that means chucking the filibuster and bipartisanship, so be it.

Four things are pushing Biden to jam through what could amount to a $5 trillion-plus overhaul of America, and vast changes to voting, immigration and inequality.

1. He has full party control of Congress, and a short window to go big.
2. He has party activists egging him on.
3. He has strong gathering economic winds at his back.
4. And he’s popular in polls.

Presidential historian Michael Beschloss told Axios FDR and LBJ may turn out to be the past century's closest analogues for the Biden era, "in terms of transforming the country in important ways in a short time."

• Beschloss said the parallels include the New Deal economic relief that Franklin Roosevelt brought in 1933, which saved the country from the Depression and chaos.
• And Biden is on track to leave the country a different place, as Lyndon Johnson did with his Great Society programs.

People close to Biden tell us he’s feeling bullish on what he can accomplish, and is fully prepared to support the dashing of the Senate’s filibuster rule to allow Democrats to pass voting rights and other trophy legislation for his party.

• He loves the growing narrative that he’s bolder and bigger thinking than President Obama.
• This temptation to go even bigger, Senate Republican Leader Mitch McConnell insists, will create such a fissure between the parties that he compared it this week to "nuclear winter."

But we're told Biden won’t hesitate. Just as he passed the $1.9 trillion COVID rescue package with zero Republican votes and zero regrets, his team sees little chance he's going to be able to rewire the government in his image if he plays by the rules of bringing in at least 10 Republicans.

• He won't rub their noses in it, we're told. That'll be the Biden touch to rolling the opposition — and getting that much closer to the status of latter-day FDR.