Danny Wild / USA Today Sports / Reuters

Before a president begins thinking about who should be his White House chief of staff, he has to define both the job and the moment. There’s nothing magical about the chief of staff’s corner office in the West Wing. How any individuals perform in the job depends, first, on the power the president gives them to execute their responsibilities, and second, on their expertise facing whatever’s in front of the White House in that moment. So how should that inform President Donald Trump as John Kelly takes his leave?

Consider the first issue. Had they been given unlimited time and bandwidth, neither of the presidents I worked for would have even hired a chief of staff. Presidents Bill Clinton and Barack Obama would have wanted to take every meeting, hear every perspective, mull every decision, game out every scenario, and address every challenge. They both loved the job of president—and arrived in the Oval Office every morning excited to see what they could accomplish.

But both also recognized that they simply couldn’t do it all. No president can. To get anything completed, and certainly to get the most important things done, they needed to discipline their own time and attention. They needed a gatekeeper. They needed someone to play traffic cop inside the bureaucracy. Without someone wielding the organizational tools that keep the executive branch moving apace, an administration can devolve into chaos. And so, however begrudgingly, both Clinton and Obama accepted that the limitations their chiefs of staff would impose on them and the rest of their administration would help them achieve their goals.

That’s simply not how Donald Trump does business—never has been. Does someone need to impose order on the West Wing? The answer is obvious. But it wouldn’t matter whom you put in the job—George Patton, Angelo Dundee, Judge Judy, Darth Vader. If the president is going to outsource significant authority to Jared Kushner, Ivanka Trump, and other staffers, and allow them to report directly to him, no chief of staff can perform the role as other presidents have utilized it.

Second, consider the context. Obama installed me as his first chief of staff because he needed to hit the ground running to pull the country out of the Great Recession and drive the most progressive agenda since the Great Society. Having worked for Clinton, I already understood how the White House machinery worked. I knew the legislative landscape well, having been a member of the House Democratic leadership. And the president-elect trusted me because of our history working together in Illinois politics. On paper, at least, I appeared to be right for that moment, just as Howard Baker, who had been Senate majority leader, was uniquely equipped to lead Ronald Reagan’s White House during the Iran-Contra scandal. Chiefs of staff have to be paired against the challenges of their moment.

It appears that Trump is choosing a chief of staff based primarily on whether he’s equipped to help with his reelection effort. But let’s be honest—that shouldn’t be the president’s most immediate concern. He’s got other battles to fight before he can even think about 2020. The remarkable access his Cabinet appointees have given to a range of special interests—including oil companies and polluters—over the past two years will make him subject to intense scrutiny from House Democrats. President George W. Bush’s legacy was tarnished by the lackluster performance of his FEMA chief, Michael Brown, in the aftermath of Hurricane Katrina. Trump needs a chief of staff who can reassert control over Cabinet agencies, containing these potential scandals and minimizing the potential for more, regardless of whether he or she has an interesting take on the latest polling out of Michigan and Pennsylvania.

Moreover, the next chief of staff is likely to be in office when the Mueller report comes in for a landing. The days, weeks, and months that follow will present a challenge unique in the history of the modern presidency. To survive, Trump will need a true wartime consigliere—someone capable of managing the substantive, political, and public-relations challenges of what is likely to be an incredibly damaging set of allegations. There’s no reason to believe that true wisdom about when to stand tall and when to duck coincides with the capacity to conjure up quippy dog whistles. In moments of chaos, the White House will need a steady hand.

What does this mean for the rest of us? Primarily, it means we should stop asking who’s finally going to get Donald Trump under control. No one is. Self-discipline is not in the guy’s DNA. This is a White House unlike any other, and it will be for at least another two years. Kelly’s replacement won’t really be the chief of staff, even if that’s what it says on his door; Trump is unwilling to give anyone the authority needed to perform that job.

But with Trump unlikely to choose the chief of staff he needs for this moment, what’s important is that the next chief of staff be unusually good at protecting the rest of us from the president’s penchant for self-destruction. That, more than anything else, should be the primary gauge of his or her success. To whoever gets the job, I simply say, Godspeed.

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