UPDATE (11/30/16, 3 p.m. ET): On Tuesday evening the Associated Press reported that Pence, not Trump, is receiving near daily intelligence briefings, and that Trump has received just three such briefings in the four weeks since he won the presidential election.

America’s first vice-president, John Adams, said of the job: “The vice-presidency is the most insignificant office that ever the invention of man contrived or his imagination conceived.” Well, not if Donald Trump has anything to say about it. If Trump gives his vice-president, Mike Pence, the same offer he allegedly gave Ohio governor and former presidential candidate John Kasich back in July — that is, to run the country while Trump focused on “making America great again” — Pence could effectively be in charge of all domestic and foreign policy. In 2017, the vice-president of the United States could become the most powerful person in America.

Yet again, Trump would be breaking with historical precedent. From the time of George Washington to the mid-1960s, the vice-presidency was notable only for its relative meaninglessness. Before the 12th Amendment was added to the Constitution in 1804, requiring the Electoral College to vote for a president and vice-president separately, the vice-presidency was quite literally a second-place trophy — the prize for being the runner-up (under the old rules, Hillary Clinton would have been Trump’s vice-president). Even after the ratification of the amendment, vice-presidents were, at best, ignored. “For most of the office’s history, [the vice-presidency’s] defining characteristic has been its total lack of power,” Kevin Kruse, professor of history at Princeton University, told MTV News. “John Nance Garner, Franklin Delano Roosevelt’s first vice-president, said the office wasn’t worth ‘a bucket of warm piss,’ while FDR’s last vice-president, Harry Truman, said it was like being ‘a cow’s fifth teat.’”

This meant that for decades, vice-presidents were often the last to learn critical information. As vice-president, Harry Truman wasn’t told about the Manhattan Project — the secret World War II plan to construct an atomic bomb. In 1943, when Truman inquired about a suspicious weapons plant in Minneapolis (which was connected to the Project), he received a phone call from then-President Roosevelt’s secretary of war telling him to stop asking questions. Only upon Roosevelt’s death — when Truman became president — was he told anything about the existence of a weapon so powerful it would decimate two major Japanese cities.

But as the power of the presidency has expanded, expectations for vice-presidents have grown as well. Following the rise of two former vice-presidents (Lyndon B. Johnson and Richard Nixon) to the highest office in the country, presidents started taking vice-presidents more seriously. In turn, recent vice-presidents like Dick Cheney and Joe Biden have had more policy-making responsibilities — and added influence. For example, Cheney strongly promoted the invasion of Iraq in 2003 — ultimately shaping then-President George W. Bush’s approach to the war — because he believed (wrongly) that there was a link between Iraqi dictator Saddam Hussein and the terror group al-Qaeda, the perpetrators of 9/11. Biden was in charge of shepherding the American Recovery and Reinvestment Act — more than $787 billion in stimulus funds — through Congress during Obama’s first term.

A Pence vice-presidency, however, would be a radical departure from the past. “What Trump has proposed with Pence,” Kruse said, “is entirely different. ... As Trump has described it, his vice-president would run things like an acting president, under the terms of the 25th Amendment. Trump would nominally remain president, but Pence would handle all the actual duties. Basically, he’d be the decider, not Trump.”

That would put Pence in the driver’s seat on setting policy priorities and mediating the White House’s relationship with Congress. The good news is that Pence appears to be capable and consistent. The bad news is what he could be capable of; Pence is the most conservative vice-presidential pick in half a century, per the American Conservative Union, supporting major tax cuts, massive increases in defense spending, an end to environmental regulations, and overturning Roe v. Wade. With the GOP firmly in control on Capitol Hill (holding majorities in both the House of Representatives and the Senate), he could get a Republican wish list signed into law — even if Trump doesn’t agree with it. While his boss focuses on “making America great again” at victory rallies, Pence will be laser-focused on imparting a conservative agenda that’s more Paul Ryan than populist — that is, more focused on cutting government spending than starting trade wars with China. Trump might have touted a $1 trillion infrastructure bill to fix America’s tunnels, roads, and airports during the campaign, but Pence and other GOP stalwarts likely won’t get on board. And Trump’s newfound support for the Affordable Care Act might not survive Pence, who has demanded its repeal while requiring it to be modified while in office as governor of Indiana.

In short, for the first time in American history, the vice-president will have the most important job in Washington. Trump may have wanted to win the election, but there’s been no real sign he wants to lead the country. That means that the actual power in the White House won’t be the one that’s on late-night Twitter — it’ll be the one that’s on Air Force Two.