With a Republican president in the White House who prides himself on cutting regulations, Sen. Elizabeth Warren (D-Mass.) took a far different tack on Tuesday, robustly defending government rules as essential to the well-being of Americans.

In a speech, Warren, a potential 2020 challenger to President Trump, called his deregulatory agenda a corrupt boon to corporate interests and argued that well-crafted rules foster consumer protection, workplace safety and a better environment.

“Don’t tell me that all rules do is restrict freedom,” Warren said in a speech delivered at Georgetown Law School. “Good rules empower people to live, work and do business freely and safely. . . . Government matters, and we cannot be afraid to say so.”

Aides said the speech was the first in a series Warren will deliver over the next month about the need to address corruption in Washington, and she promised to offer “sweeping” legislation on the subject.

Tuesday’s speech served as an early marker in what is expected to be a large and amorphous field of potential Democratic candidates seeking to offer policies that distinguish themselves from one another and the current occupant of the White House.

Warren bemoaned the regulations that Trump has rolled back, including more than 60 that she said have weakened clean-water and other environmental protections at the behest of corporations.

“President Trump and his team have embarked on an aggressive effort to kill the rules that protect the American people from corporate predators,” Warren said, singling out Environmental Protection Agency administrator Scott Pruitt for particular scorn.

“Corruption oozes out of his office,” Warren said.

She said that as a presidential candidate in 2016, Trump had led voters to believe that he would “drain the swamp” in Washington, fight for working people, ignore lobbyists and stand up to Wall Street.

“It is clear now that those promises were just part of the scam, a scam that has paid off handsomely for Wall Street, paid off handsomely for every corporation that can hire an army of lobbyists or drop big money at a nearby Trump hotel,” Warren said.

She recounted the history of a U.S. regulatory environment that she said came under assault during the Reagan administration and is now at risk again, lamenting that regulators have become viewed as enemies by Republicans.

“Where are the defenders of regulators who make sure that most of us don’t work in factories where equipment could kill us or don’t drive cars with defective brakes?” Warren asked.

“Where are the parades and the special citations for the federal employees who make sure that cancer treatments really are cancer treatments and that the air is clean enough for our babies to breathe and grow and flourish?” she continued. “Where are the thank-you op-eds and the national holiday to celebrate that infants are no longer strangled in poorly designed baby cribs and that airplanes rarely crash?”

Warren’s speech was part of symposium by an organization called the Coalition for Sensible Safeguards.