Reince Priebus got the boot as White House chief of staff because, among other things, the staff was fighting openly among its members.

Donald Trump enlisted Homeland Security Secretary John Kelly to right the ship. Kelly signed on as chief of staff, kicked out some of the troublemakers and settled into his new gig as the president’s keeper.

Then came the midterm election. It didn’t go quite so well for the president and the Republican Party. The battling within the White House resumed.

Kelly now is among those closest to the president who not only is involved in some of the rhetorical brawling, he might be on the short list of key staffers about to be shown the door.

His successor at Homeland Security, Kirjsten Nielsen, is thought to be on the bubble. Defense Secretary James Mattis, too. Same with Interior Secretary Ryan Zinke. Media are reporting that press secretary Sarah Sanders might depart by the end of the year. Rumors also are flying about Education Secretary Betsy DeVos’s future.

Now we have first lady Melania Trump engineering the departure of national security adviser John Bolton’s top aide. Holy moly, man!

Have I mentioned that the president’s “fine-tuned machine” is in need of a serious lube job? There. I just did.

John Kelly pledged to stay through the 2020 election. It looks now as though that pledge won’t bear fruit. What do you suppose might be driving him away? Is it the president’s SNAFU over declining to visit the cemetery containing American servicemen who died in World War I? Is the ongoing chaos that keeps the White House in a state of constant upheaval?

Whatever it is. Whatever is troubling the entire staff is likely to bring another wave of resignations/dismissals.

Get the grease gun for that White House machine.