Last Monday, Dan Driscoll walked into the Oval Office to tell President Trump he was resigning as Secretary of the US Army after just 18 months in the job. Trump asked him to stay until after the midterms; Driscoll replied that Wednesday was his last day.

But he had a message for the president. Pete Hegseth, the Pentagon’s chief, was well on his way to destroying the US Army. His firings of high-level generals, including the army chief of staff, and the defense secretary’s repeated interference in the promotion process had left a senior officer corps uncertain about their future and the rank and file concerned about who would lead them into combat.

Driscoll’s warning to the president is hardly the only signal that something is profoundly amiss at the Pentagon. Indeed, the concern is both broader and deeper. In the 18 months since returning to office, Donald Trump and Hegseth have presided over the US military in ways that have left it profoundly weaker than when they found it.

One reason is Hegseth, whose leadership Senator Thom Tillis called “the most inept management” he’d ever witnessed. He accused the defense secretary of being “intimidated by competence” and of “ginning up culture wars”. Tillis is right – though all of this was well known and documented at the time the Fox News weekend host was nominated by Trump and Tillis cast the deciding vote for his confirmation.

Hegseth has singularly focused on rebuilding the US military in his own image. He launched an anti-Diversity, Equity, and Inclusion (DEI) crusade on day one, resulting in the firing of top black and female officers, including the Chairman of the Joint Chiefs of Staff and the Chief of Naval Operations. He heralded a warrior culture based on a cartoon image of the tough soldier: white, male, muscular, beardless, crewcut, tattooed and Christian. And his attempt to boost troop morale was to challenge them to pushups and sprints.

Nothing underscores Hegseth’s flawed priorities more than his decision last September ordering 80 flag officers to leave their posts, at great risk to global readiness, to hear a tirade by the defense secretary about “fat troops” in combat formations and “fat generals and admirals” in the Pentagon. This is what Hegseth’s leadership of the greatest military in the world has come to. No wonder Driscoll decided he’d had enough.

The second reason for the decline of the US military is the way it has been used, especially in the past six months. The Iran war, which Hegseth was the primary senior official to support without hesitation, has turned not only into a strategic disaster of historic proportions, with Iran in a strategically stronger position than it was before, but has severely weakened military readiness for more pressing contingencies.

The war has been a black hole for American munitions, not least costly air defense interceptors. Though exact figures remain classified, various reports indicate that the inventory of Patriot interceptors is a third of the prewar total, and the costly THAAD missile inventory may be down by as much as 80%. A quarter of the Air Force’s Reaper drone fleet is gone. Replenishing stockpiles will take years. At present, THAAD production runs below 100 a year. The administration has requested 857 for next year alone and nearly 2,600 over five years — a target that, at current output, would take 27 years to fill. On Saturday it emerged that the US government had taken the extraordinary step of subjecting around 50 members of the military’s Joint Staff to polygraph tests over leaks to the media about the depletion of munitions stocks.

Readiness has suffered drastically as well. The US Navy’s top officer, Adm Daryl Caudle, has warned that barely a quarter of the destroyer fleet is fit to deploy — and other service chiefs have formally “non-concurred” with orders extending their forces into 2027, objections Hegseth has simply overridden. The aircraft carrier Gerald Ford came home in May after 326 days at sea, the longest deployment since Vietnam, and now needs the better part of a year in the yard before it can sail again. The Army’s Patriot air-defense crews have watched their standard nine-month rotation become 12. Re-enlistment rates are bound to suffer as a result – pointing to long-term damage to the force.

The costs are landing hardest exactly where Washington can afford it least. The new forever war with Iran is sapping critical resources from more pressing theatres. Just as China is upping the ante on Taiwan and Russia is escalating in Ukraine and beyond, the US has pulled critical capabilities from these regions to bolster capabilities in the Gulf well into 2027. The US pulled its one aircraft carrier in the Pacific to the Arabian Sea, critical air defense capabilities have been redeployed from Korea and Germany to protect US bases throughout the Middle East, and the Marines quietly canceled their biennial amphibious exercise with South Korea, citing the same Gulf demands.

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It’s far from clear that the US could today handle an Asia or Europe contingency effectively – let alone both at the same time. Faced with a weakened US military and strained alliances, Beijing and Moscow may well be calculating that the window for decisive action has opened wide, thus increasing the chance of war.

Trump has for years boasted that he “completely rebuilt“ a military that is “stronger than ever before”. But after 18 months – with a defense secretary his own party wants gone, munitions stocks that will take years to rebuild and a fleet stretched thin across three continents – what Trump has created is a hollowed-out force that is far less able to meet the rising threats to US and global security.

Ivo Daalder is the former United States Permanent Representative to Nato

Photograph by Bloomberg via Getty Images