Want to quit the Trump Cabinet? Get in line.

(CNN)On Thursday, President Donald Trump and Department of Homeland Security boss Kirstjen Nielsen got into a very heated argument about whether she was doing enough to enforce the President's immigration policies.

In the wake of that set-to, Nielsen, according to the New York Times, told colleagues she was on the verge of resigning. (DHS has denied that Nielsen was considering quitting although no one takes issue with the reporting on the fight between Trump and her.)
Assuming Nielsen did think about walking away, she would be in good company. Of the 16 members of Trump's current Cabinet, which includes Vice President Mike Pence, 25% have threatened or offered to resign: Nielsen, Attorney General Jeff Sessions, Chief of Staff John Kelly and Defense Secretary Jim Mattis.
Four former Cabinet members also either threatened to resign or actually did it. They include Secretary of State Rex Tillerson, Health and Human Services Secretary Tom Price, Veteran Affairs Secretary David Shulkin and chief of staff Reince Priebus.
    According to Brookings' Kathyrn Dunn Tempas, who is tracking turnover among senior officials -- including members of the Cabinet -- more than 1 in 3 of these "A-level" people left the Trump administration in its first year. Total attrition in Trump's first 16+ months in office is a whopping 49%.
    That level of departures -- particularly so early in an administration -- is historically anomalous, again according to data gathered by Dunn Tempas.
    Here's the rate of turnover for the first year of the five previous presidents: Obama 9%, Bush 6%, Clinton 11%, Bush 7% and Reagan 17%. Remember that Trump's first year turnover was 34% -- and that number has soared to 49% when you consider his 16 months in office.
    The pace at which Trump is running through staff isn't terribly surprising. Throughout his life, Trump has made no apologies for a management style that seeks to pit people who work for him against one another in a sort of Thunderdome battle in which Trump offers final judgment.
    "I like having two people with different points of view, and I certainly have that," Trump said in March. "And then I make a decision. But I like watching it. I like seeing it. And I think it's the best way to go."
    It may be the best way for Trump to go. But, the constant fighting, chaos and Trump's tendency to publicly undercut or even bully members of his Cabinet doesn't seem to be wearing well among those who work for him.
    Trump, of course, has never expressed much concern in people who leave. Back in November 2017, he was asked about the large number of ongoing vacancies within his administration. "Let me tell you, the one that matters is me," Trump said. "I'm the only one that matters, because when it comes to it, that's what the policy is going to be. You've seen that, you've seen it strongly."
    In short, Trump sees himself as sui generis. He is everything he needs. He is a rock, he is an island.
    All of which means that you can expect more resignations -- threatened and real -- as Trump's time in the White House proceeds. And Trump will continue to express zero concern about it because, well, he'll still be there.