There are about 2 million people who work in the federal government. Despite being in charge of the executive branch, the president is limited in the people he can unilaterally fire.
But could that all be about to change?
In Brett Kavanaugh, President Trump has nominated someone to the Supreme Court who, like he, believes in an expansive view of presidential power.
Could the president hire and fire civil servants at will, for example? That question is at the heart of a concept that likely will come up often at Kavanaugh's confirmation hearings this fall.
Trump has sought to exercise a degree of unilateral power over the federal government, perhaps more than any president in modern times. Though many of his moves have been blocked in the courts, he is aiming to change the courts through appointments, and by his nominees to the Supreme Court.
First, it was Neil Gorsuch, and now, Kavanaugh, both of whom have long believed that presidential powers have been unconstitutionally weakened over most of the last century.
They believe in something called the "Unitary Executive." Yes, the phrase sounds like legal gobbledygook. But it boils down to the idea that the president should be able to, for any reason, fire the heads of various departments that have executive powers.
That would include quasi-independent agencies like the Federal Trade Commission, the Securities and Exchange Commission and the Nuclear Regulatory Commission.
These agencies were created by Congress to be independent, their work subject only to court challenge. Most have five commissioners appointed by presidents from both parties and confirmed by the Senate with both fixed and staggered terms.
The sitting president gets to pick the chairman, but, by law, no more than three commissioners can come from one party.
The idea of independent commissions was challenged in the 1930s when President Roosevelt tried to fire a Federal Trade commissioner, William Humphrey, appointed by his Republican predecessor. Roosevelt didn't have any quarrel with Humphrey's job performance, but he fired him over policy disagreements. So Humphrey challenged the firing in court.
In a landmark, unanimous decision, the Supreme Court ruled in favor of Humphrey, to the great consternation of Roosevelt.
In the 1980s, it was conservative Republicans who sought to rein in the idea of independent officers, but they lost. Now comes a second generation of that effort, spearheaded by leading conservative judges, most prominent among them, Kavanaugh.
"It's based on the idea that somebody's gotta control these people, including the independent agencies," University of Chicago law professor Eric Posner of the unitary executive idea. "In a democracy, that person should be subject to popular election, and that's the president."
The alternative view, he said, is that you want to have some parts of the bureaucracy "that are not under the president's thumb, so that those people would be able to act in a non-partisan way, in an expert way."
'A huge shift in how the federal government does its job'
University of Texas law professor Steven Vladeck argues that quasi-independent agencies are able to do their jobs, because they are not subject to the moment-to-moment political whims of the White House.
"If that changes, I think we'd see a huge shift in how the federal government does its job," he said, "and more perniciously, we'd see a further politicization of just about every decision that the federal government is making."
Kavanaugh has a contrary view.
"He's definitely highlighted the problems inherent in taking administrative power and disconnecting it, at least in part, from the president's oversight," said Adam White of the conservative Hoover Institution.
Indeed, Kavanaugh has criticized the Supreme Court's unanimous decision in the 1935 Humphrey case, though he has not outright advocated its reversal. He has, however, clearly suggested that a president ought to be able to fire anyone performing executive functions, based solely on policy differences.
The Trump administration is aggressively pushing the unitary executive idea, aiming its legal arrows at independent officers within agencies.
This year, the administration argued that position in the Supreme Court, winning a partial victory, but less than it asked for. The court ruled that independent administrative law judges at the Securities and Exchange Commission must be hired by the commission — not, as previously had been the case, selected on the basis of merit-based examinations conducted by the Office of Personnel Management.
The court, however, did not go further and say anything about firing. Trump, nonetheless, issued an executive order and the Justice Department has issued guidelines, allowing the firing of administrative law judges who "fail to follow agency policies, procedures, or instructions."
In short, the judges, referred to as ALJs, can be fired pretty much whenever they don't follow orders. As the Justice Department guidelines put it, in the future, the government will argue in court that these new rules give the president "a constitutionally adequate degree of control over ALJs."
What are administrative law judges and what do they do?
There are 1,900 ALJs in independent agencies and executive departments. They hear cases involving everything from Social Security to stock fraud claims.
There are thousands more who hold similar positions, administrative judges within the executive branch who preside over everything from immigration hearings to benefit claims for black lung disease.
Legal experts on the left and right see the new rules as an effort to tee up cases for a new, and more conservative, Supreme Court majority, a court majority more hospitable to broad presidential power.
Just how far down could the new rules granting broad executive control go?
"That's always been a question," said Columbia Law School professor Gillian Metzger. "Does it go to the civil service?"
Administrative law judges have always been seen as "more on a par with civil service employees," she observed. "So it really does start to raise a question of whether the civil service protections might also be at risk."
The Hoover Institution's White isn't sure whether Kavanaugh would go that far.
As for Metzger, she said a "hardcore unitary executivist would say" all government employees "could be removable by the president. Whether Kavanaugh goes that far, I don't know."
NPR's Domenico Montanaro contributed to this report.