Because the United States has long been the world’s preeminent superpower, the U.S. Armed Forces maintain combatant commands around the globe. Those who lead these commands might not be known to the public, but they hold unique and powerful positions.

The head of European Command, for example, coordinates U.S. military planning and operations in and around the continent. There are related posts for Africa Command, Central Command in the Middle East and so on.

U.S. Southern Command, which is responsible for overseeing Central and South America, has been of particular interest lately — in part because Donald Trump has ordered a series of deadly military strikes against civilian targets in international waters, and in part because the Republican president has escalated tensions with Venezuela to an unsettling degree.

Indeed, just in recent days, the White House has authorized new intelligence operations in Venezuela and reportedly flown an elite Special Operations aviation unit near the Venezuelan coast. Meanwhile, The Wall Street Journal reported that Venezuela is “moving troops into position on the Caribbean coast and mobilizing what President Nicolás Maduro asserts is a millions-strong militia in a display of defiance against the biggest American military buildup in the Caribbean since the 1980s.”

The head of Southern Command, in other words, has a critically important job right now. So it’s significant that the Navy admiral in this leadership post announced that he’s stepping down. The New York Times reported:

The officer, Adm. Alvin Holsey, is leaving his job as head of the U.S. Southern Command, which oversees all operations in Central and South America. … It was unclear why Admiral Holsey is suddenly departing, less than a year into what is typically a three-year job, and in the midst of the biggest operation in his 37-year career.

Naturally, there’s been a great deal of speculation about what may have prompted the admiral to quit, though the mystery appears to have an answer. The Times referenced two sources who said Holsey “had raised concerns about the mission and the attacks on the alleged drug boats.” CNN ran a related report, noting that the SouthCom chief had privately expressed reservations about the legality of the Trump-approved strikes.

And while MSNBC hasn’t independently verified that reporting, if accurate, it paints a rather dramatic picture. Sen. Jack Reed of Rhode Island, the top Democrat on the Senate Armed Services Committee, said in a written statement, “At a moment when U.S. forces are building up across the Caribbean and tensions with Venezuela are at a boiling point, the departure of our top military commander in the region sends an alarming signal of instability within the chain of command.”

Complicating matters is the sheer volume of U.S. military leaders who’ve left Secretary Pete Hegseth’s Defense Department, either through firings or resignations. Indeed, just days before Holsey stepped down at SouthCom, the Pentagon chief fired Navy chief of staff Jon Harrison. (His ouster roughly coincided with two high-profile military retirements — Gen. Bryan Fenton, the head of U.S. Special Operations Command, and Gen. Thomas Bussiere, a top Air Force commander — though it’s unclear if their departures had anything to do with Hegseth.)

There was no ambiguity, however, in late August when the defense secretary fired Lt. Gen. Jeffrey Kruse, who served as director of the Defense Intelligence Agency, and Rear Admiral Milton Sands, a Navy SEAL officer who oversaw the Naval Special Warfare Command.

Four days earlier, Gen. David Allvin, the chief of staff of the Air Force, was also shown the door.

The broader purge also includes Air Force Gen. Timothy Haugh, who was both the head of U.S. Cyber Command and the director of the National Security Agency; Gen. Charles Q. Brown Jr., who was chairman of the Joint Chiefs of Staff; Gen. James Slife, former vice chief of staff of the Air Force; Adm. Linda Fagan, the commandant of the U.S. Coast Guard; Adm. Lisa Franchetti; Lt. Gen. Jennifer Short; Lt. Gen. Joseph B. Berger III, the Army’s top military lawyer; Lt. Gen. Charles Plummer, the Air Force’s top military lawyer; and Navy Vice Adm. Shoshana Chatfield, the only woman on NATO’s military committee.

Each of these instances is important in its own right, but let’s not miss the forest for the trees: A scandal-plagued former Fox News host appears to be destabilizing the U.S. military.

Toward the end of his unsettling speech to the nation’s generals and admirals a few weeks ago, in which his argument boiled down to the assertion that testosterone is the key to modern warfare, Hegseth delivered an unsubtle message to his audience. “If the words I’m speaking today are making your heart sink, then you should do the honorable thing and resign,” the secretary said.

Those words continue to resonate for a reason.

This post updates our related earlier coverage.