“After four years of Donald Trump,” declared Senator Amy Klobuchar in a statement on Tuesday, “a new president can’t wait for a bunch of congressional hearings to act.” To that end, the Minnesota Democrat, who hopes to become the new president in January 2021, issued a 16-page list of all the “concrete steps she will take in her first 100 days” if she is elected to the White House.

Some of Klobuchar’s promises are wholly conventional (“Visit our troops”) or matters of routine management (“Reduce State Department vacancies”). A few are about as noteworthy as calling water wet (“Fill judicial vacancies”).

Many, however, would represent real shifts in US policy. Klobuchar’s pledges include the immediate importation of prescription drugs, a boost in the hourly minimum wage for federal contractors to $15, an end to the trade embargo on Cuba, the addition of transgender identity as a protected civil rights category, and a return to the Iran nuclear deal. Those aren’t modest adjustments; they would significantly change the way the federal government currently operates. Obviously that’s Klobuchar’s objective — and for many voters, the undoing of President Trump’s work can’t begin soon enough.

But do Americans really want their government to operate on the basis of unilateral presidential decrees? When Klobuchar dismisses any thought of waiting “for a bunch of congressional hearings” before upending the government’s priorities and principles, what she is really dismissing is the constitutional order, which puts Congress, not the president, in charge of changing US law. There is nothing ambiguous about Article I, Section 1 of the Constitution. “All legislative powers,” it begins, “shall be vested in a Congress of the United States.” All — not just the ones a president isn’t too impatient to wait for. Yet Congress is almost an afterthought in Klobuchar’s approach.

The senator from Minnesota is far from alone. Most of the leading Democratic presidential candidates are vowing to bypass Congress and use executive orders to get what they want.

Senator Elizabeth Warren says that on her first day as president, she’ll order a “total moratorium” on new fossil fuel leases, closing the door to drilling for energy offshore and on public lands. Senator Bernie Sanders will ban companies that outsource American jobs from qualifying for federal contracts. Beto O'Rourke would direct US officials to release from detention any undocumented immigrants with no criminal background. And Kamala Harris threatens an ultimatum: If members of Congress don’t “get their act together” and pass new gun-control laws within 100 days of her inauguration, she warns, she will impose the restrictions without them.

This tide of executive unilateralism rises with each incoming president.

George W. Bush authorized the use of “enhanced interrogation techniques,” including waterboarding and other practices widely considered torture, notwithstanding the prohibition of torture under longstanding US law and treaty. Barack Obama insisted many times that he had no authority on his own to waive the deportation of youthful undocumented immigrants — but then did so anyway by executive order in 2012. After Congress refused to fund a massive wall on the Mexican border, Trump declared that a national emergency empowered him to spend the money just the same.

For every such high-profile example of a president making law by edict, many more occur out of the spotlight. Increasingly, the vast powers of the federal bureaucracy are deployed not as Congress directs through legislation, but as presidents command through executive order. One of the first priorities of each incoming president now is to sign a slew of new directives countermanding the old ones. Before Trump entered the White House, he excoriated his predecessor for “constantly issuing executive orders that are major power grabs.” That hasn’t stopped him from spending the last 30 months engaged in power grabs of his own. It won’t stop his successor from going even further.

This is not a partisan complaint. Democrats and Republicans are equal offenders. Presidents are growing more and more autocratic, and that should alarm all Americans, whatever their political leanings. “The natural progress of things is for liberty to yield and government to gain ground,” Thomas Jefferson wrote in 1788. Could even he have imagined, though, just how much liberty Americans would eventually yield? Or just how much power they would allow presidents to amass?

There was a time when even the most dominant presidents took it for granted that they could not simply act without regard to Congress. At the outbreak of the Civil War, Abraham Lincoln had no choice but to move unilaterally, since the nation was under attack and Congress was out of session. But as soon as legislators returned to Washington, he took pains to secure congressional legitimacy for his actions. The same was true of Franklin Roosevelt. “Even through the World Wars and Depression,” writes Bruce Cannon Gibney in The Nonsense Factory, his sweeping new study of America’s legal system, “FDR accomplished most of his work through Congress … returning time and again to Congress and voters for support.”

Today’s presidents and would-be presidents, by contrast, make no secret of their intention to sidestep Congress. We can keep letting them get away with it. But an ever-more-overbearing presidency is not a recipe for American happiness. If that isn’t clear yet, just wait.

(Jeff Jacoby is a columnist for The Boston Globe).