Is President Joe Biden living up to expectations? It’s hard to say, since the expectations generated on his campaign trail were so murky. Biden made plenty of promises on the stump but only one thing was ever clear: he wasn’t Donald Trump. Beyond that, no one was really certain what iteration of Biden would enter the Oval Office on Inauguration Day. A pragmatic moderate or a progressive ideologue? A return-to-normal steady hand or a malarkey-scourging bomb thrower? The law-and-order author of the PATRIOT Act or the ‘Black Lives Matter’ anti-racist he suddenly morphed into last summer?

Biden was so defined by who he wasn’t that no one ever quite worked out who he was. Now we have our answer. Whatever moderation was once attributed to him has been quickly abandoned. The Keystone XL Pipeline has been canceled, the radical Equality Act has been endorsed, the Paris Climate Agreement has been rejoined. Most glaringly of all, one of the largest spending bills in American history has been signed into law, with promises of much, much more to come. Most recently, Biden has been haggling with the GOP Congress over his proposed infrastructure package. He wants $2.3 trillion while the Republicans have said they could go as high as $800 billion and even raise the gas tax in order to pay for it.

It’s a stunning dynamic, both because the GOP once filleted Barack Obama for trying to pass a stimulus package of about that same size (though in 2008 dollars) and because of the even higher total that the president is demanding.

So who is Joe Biden? Right now, he’s the most fiscally irresponsible president in American history. Many on the left trace an unbroken thread from FDR to LBJ to Barack Obama, all progressive Democrats who took an activist approach to government and spent big money trying to solve big problems. Biden clearly views himself in this tradition rather than in the more conservative and restrained one of Jimmy Carter and Bill Clinton.

Yet there’s more going on here than mere self-indulgent FDR LARPing. Biden is a product of a post-2008 Washington that increasingly feels no constraints on its ability to spend. With interest rates and inflation having remained low for over a decade, there haven’t been any serious consequences for eye-watering deficits and national debt. In retrospect, this has proven one of the most consequential political developments of the 21st century. It’s effectively dried up both the right’s fiscally conservative streak and the left’s erstwhile desire for ‘good government’. It’s thrashed the Tea Party, cemented a humongous federal bureaucracy, and led to the largest national debt since World War Two.

Yet all of a sudden this artery-clogging free lunch may be coming to an end. The latest report from the Consumer Price Index saw prices soar by 4.2 percent, the sharpest spike since 2008 and a harbinger of inflation. With Americans poised to unleash a wave of pent-up money this summer, the old problem of too many dollars chasing too few goods could become a serious one. Even left-wing economists agree that inflation acts as a curb on federal borrowing. That means if it continues, it could force Biden to do the absolute last thing he wants to do: cut back.

The man who thinks he’s FDR could be dropped into the loafers of Calvin Coolidge.

At least for now, Biden is largely in denial about this potential change. He’s shown no inclination to shut off the federal spigot, forging ahead with a combined new $4 trillion in federal spending, an insanely reckless move as inflation mounts. This is ideological madness — Democrats have turned big spending into an end unto itself — but it’s also a high-stakes wager. Biden is effectively gambling that inflation won’t become the major problem some are predicting it will, that the economy has plenty of room yet for the further trillions he wants to dump into it.

He could end up being right — we’ll find out as the summer progresses — but he could also end up being very wrong and have no choice but to kick his spending habit.