When President Donald Trump dropped the bizarre suggestion last week that the military should use American cities as “training grounds” to fight what he called “an enemy within,” it sounded almost like old news.

After all, Trump has talked like this for years. “Don’t take him literally,” some would say. Or, that’s just Trump being Trump.

Yet for the past couple of months Trump has been foreshadowing the deployment of National Guard troops to Chicago and Portland, and as I write this citizens of those cities are watching and waiting for it to happen, just as he sent troops to Los Angeles, Washington, D.C., and Memphis, purportedly to crack down on crime and support immigration enforcement.

But there was a distinct difference in gravity to Trump’s rambling at Quantico. He was making his suggestion to a highly unusual gathering of hundreds of the nation’s top military leaders — admirals, generals, top sergeants — who were summoned from around the world, on short notice, to Marine Corps Base Quantico in Virginia by Secretary of Defense Pete Hegseth, for a purpose most could only guess at before the meeting.

Trump, a late addition to the program, apparently could not pass up an opportunity to address military commanders on national television — and appeared to be visibly thrown off guard by the absence of applause.

This was, after all, not a political rally — or, rather, not supposed to be. The military, especially a gathering of senior-rank officers, refrain from showing politically tinged approval or disapproval. (Alas, after speaking to countless political gatherings, the president still seems to be learning his regular job.)

Hegseth’s speech was notable for its scolding tone. Strutting back and forth in front of a giant American flag, no doubt set up to recreate the iconic scene from the movie “Patton,” Hegseth declared it was “completely unacceptable to see fat generals and admirals” in the military.

That reminded me of my own final weeks in the Army back in the Vietnam era, when our company commander threw a baleful look at my expanding tummy and noted, “You could lose a few pounds there, eh, Page?”

Sir, yes, sir!

I was a short-time draftee by then, silently counting the days until I could go home.

Hegseth’s audience, by contrast, was made up of the men and women who lead the premier fighting force on Earth. And the popinjay berating them from the stage was performing for a political audience, not for them. Hegseth and Trump would spend the day castigating liberals, and threatening to brutalize their cities, and the assembled generals and admirals were there as props. One can only imagine what was going through their minds.

Hegseth commanded troops at Guantanamo Bay and in Iraq and Afghanistan, reaching the rank of captain, but his main qualification for Trump’s Cabinet seems to have been his time working for Fox News. And in his performance at Quantico, his culture warrior chops were clearly in evidence.

“We’ve promoted too many uniformed leaders for the wrong reasons: based on their race, based on gender quotas, based on historic so-called ‘firsts,’ ” Hegseth said.

He snarled about wokeness, DEI, “dudes in dresses” and “climate change worship,” and concluded by saying “we’re done with that s—.”

Hegseth heralded the return of swashbuckling, manly warriors who “kill people and break things for a living,” and who will henceforth be liberated from “stupid rules of engagement.”

The non-military audience listened and wondered, is that a green light for war crimes? We don’t know what the generals and admirals thought. To eschew politics is their ethos and their training. Their vow is to defend the Constitution.

Yet Hegseth left little doubt that his gung-ho ideological bent is integral to how he runs the Pentagon — and that no duty requires him to check a president who talks routinely about violating the constitution and possibly turning our troops against American citizens.

“I told Pete,” Trump told his Quantico audience, “we should use some of these dangerous cities as training grounds for our military. Because we’re going into Chicago very soon. That’s a big city with an incompetent governor. Stupid governor. Stupid.”

Not stupid enough to take Trump’s bait, I hope.

Indeed, it’s hard to imagine any observer stupid enough not to see that Trump is playing a potentially deadly game with our constitutional order. And yet we don’t seem to know how to protect it from him.

I am reminded of the immortal wisdom of a figure from my childhood, the comic strip character Pogo: “We have met the enemy and he is us!’

It’s an old line but unfortunately still powerfully relevant.

(E-mail Clarence Page at clarence47page@gmail.com.)