President-elect Donald Trump speaks in Hershey, Pa. on Dec. 15. (AFP Photo/Don Emmert)

Last week, after President-elect Donald Trump named ExxonMobil chief executive Rex Tillerson as his pick for secretary of state, the transition reached a milestone of sorts. Nominations for the most prized jobs in the Cabinet -- the people who lead the Departments of State, Defense, Justice and the Treasury -- are all in place, filling what have come to be known as the "big four" jobs.

As The Washington Post wrote in 2011, these are the "original departments created by George Washington, with the heftiest portfolios" -- the most high-profile positions and among the foremost voices guiding the president's thinking on critical military, foreign affairs, justice and economic issues. And for the first time in more than two decades -- if those four names are ultimately confirmed -- the "big four" jobs will be entirely white and male.

Trump "will not be continuing the limited progress that had been made to make the inner Cabinet look like America," Anne Joseph O'Connell, a law professor at the University of California, Berkeley, told OnLeadership last week. O'Connell maintains a database of key government appointees going back to the Carter administration. "While this may be discouraging to many, it is not surprising." R

Read more analysis of the diversity at the top of Trump's Cabinet here.

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* On the day Trump said he’d clarify his business dealings, his conflicts of interest look thornier than ever (The Washington Post)