In this October 2018 photo, then-US Defense Secretary Jim Mattis listens as then-President Donald Trump answers questions during a meeting with military leaders in the Cabinet Room in Washington, DC.
CNN  — 

Former President Donald Trump’s suggestion that the US military should be?used to deal with?“the enemy from within”?on Election Day has reignited concerns about what he might ask US forces to do if he wins a second term as commander in chief.

And it is senior military leaders who served under him that have most clearly sounded the alarm about Trump.

The former chairman of the?Joint Chiefs?of Staff,?Gen. Mark?Milley, told?Bob Woodward?in?his new book?“War”?that the former president “is the most dangerous person to this?country … A fascist to the core.”

And on Thursday on The Bulwark podcast, Woodward said Gen. Jim?Mattis,?who served as Trump’s defense secretary,?had emailed him to say that he agreed with the assessment that Milley had provided Woodward. On the podcast, Woodward said the thrust of Mattis’ email about Trump was “Let’s make sure we don’t try to downplay the threat, because the threat is high.”

Trump has long had a boyish fascination with the?military, idolizing?World War II generals George Patton and Douglas MacArthur.?As a teenager, he?reveled in his stint at a military-style boarding school in New York.

Despite that?fascination,?Trump took multiple deferments to avoid service in the Vietnam War.

When he became president,?Trump staffed his?cabinet?with senior generals. He appointed Mattis, a retired four-star?general?to head the Pentagon; his chief?of staff?John Kelly?was?another?retired?four-star?general,?and two?of his?national security advisers?were three-star generals,?Michael Flynn and H.?R.?McMaster.

Trump?loves?the pomp and ceremony?of the military?and lobbied?for a massive?Kremlin-style?parade in Washington,?DC while,?he was in office. In the end,?the?parade?never happened.

Despite Trump’s bromance with the military,?senior retired generals and admirals?haven’t loved him back. Some?even?seem to think that?it is the former president who is the?real “enemy within.”?

Going back as far as four years ago, Mattis, provided a statement to The Atlantic magazine?that?“Donald Trump is the first president in my lifetime who does not try to unite the American people—does?not even pretend to try. Instead, he tries to divide us.”

Similarly, Kelly told CNN’s Jake Tapper last year that Trump is “a person that has nothing but contempt for our democratic institutions, our Constitution, and the rule of law.”

In?McMaster’s?book,?“At War with Ourselves,”?a memoir?of his time working at the Trump White?House, McMaster wrote that?in the aftermath of?Trump’s?2020 electoral defeat,?Trump’s?“ego and love of self… drove him to abandon his oath to ‘support and defend the Constitution,’ a president’s highest obligation.”

Gen. Stanley McChrystal, who revolutionized Joint?Special?Operations Command, the unit responsible for killing Osama bin Laden in?2011, wrote?an op-ed in The?New York Times three?weeks?ago?saying?he is voting for Vice President?Kamala?Harris?because of her?“character.” Unstated in?his?op-ed was?McChrystal’s assessment of?Trump, though in the past, McChrystal?has said?Trump?is?“immoral” and “dishonest.”

The leader of the bin Laden?operation was Adm. Bill?McRaven,?who?in 2020?wrote?an?op-ed?in the?Washington?Post?about Trump,?saying,?“when presidential ego and self-preservation are more important than national security — then there is nothing left to stop the triumph of evil.”

In early June 2020,?former?Chairman of?the?Joint Chiefs?Admiral Mike Mullen?wrote?in The Atlantic that he was “sickened” to see peaceful protestors?who were protesting the recent murder by police of George Floyd?“forcibly and violently” removed from around the White House.

It’s hard to think of any American president who has earned the opprobrium of?so?many senior officers.

That isn’t to say that?Trump?doesn’t?have some fans among?“his” generals.?While Trump was in office, New America, a research institution where I work, compiled public?statements for and against Trump by?retired and?active-duty?flag officers. We found?that?five?times more?flag officers,?255,?were critical of Trump,?while 54?supported?the Trump administration.

One?of Trump’s fans is?Lt. Gen. Keith?Kellogg,?who?served as national?security?advisor to Vice President Mike Pence.?Kellogg?appears in?Woodward’s?new?book?“secretly” meeting with Israeli?Prime Minister Benjamin Netanyahu?earlier?this year. After the trip,?Kellogg?told Trump, “They are?not going to go along with a?cease-fire.”

Kellogg is?one of the few senior?advisers?in the Trump White House who didn’t resign or get fired during Trump’s term in office.?Given his longstanding loyalty to Trump, Kellogg?will?likely return?to?some senior role?if?Trump?wins?in November.

If Trump?won the election,?he wouldn’t be?commander?in chief until January 20,?so he couldn’t order?the US military to do anything on Election Day,?as he suggested to Fox News.?But?if Trump were?to win the White House – which is?a?coin flip?right now?given the close race –?as commander in chief?and with a?pliable?secretary?of?defense,?he could order the?Pentagon to?do pretty much anything he wanted. According to senior officers who served under him,?that would be?a?troubling?prospect.