Donald Trump says he’ll listen to the nation’s generals about how to fight ISIS. He won’t like what they have to say.

Earlier this month, Trump said that one of his first acts as president would be to give his generals “30 days to submit a plan for soundly and quickly defeating ISIS.” He seems to think the reason ISIS stands is that the Obama administration has been too weak and feckless to give the military what it wants: the resources and freedom to crush our enemies.

He’s wrong. But the way in which he’s wrong is telling. The Republican presidential nominee has surrounded himself with retired generals whose extremely hard-line views about how to battle the terror group make them much more hawkish than the officers who are still serving — and would have to oversee the actual fighting. Those generals generally support the Obama administration’s current strategy of bombing ISIS from the air while arming and training the rebels battling on the ground.

Those generals also think that Russia, not ISIS, is the biggest threat to the US. Trump, in other words, would double down on what top brass see as the wrong war, while cozying up to the country many military leaders see as our greatest threat.

“He may be listening too much to the retired generals that are the ones closest to him, and extrapolating from them into the broader ranks of general officers,” said retired Army Lt. Gen. Dave Barno, formerly the top commander in Afghanistan. “That’s a mistake because they are extreme outliers in terms of wanting to do a lot more against ISIS.”

Think of it as the Iraq Syndrome: The long and failed war there means an entire generation of commanders are reluctant to commit large numbers of ground forces to what could be a conflict with no end. Candidate Trump will doubtlessly talk tough about ISIS at Monday’s debate, and a President Trump might expect that the military would enthusiastically want to help him “bomb the shit out of ISIS” in Iraq and Syria. The reality is that they wouldn’t.

Nothing in Trump’s public comments suggest that he grasps that the military is a fundamentally cautious institution led by men and women who are far from the warmongering stereotypes often seen in pop culture (like Dr. Strangelove’s Gen. Buck Turgidson).

Earlier this month, Trump told Matt Lauer that he’d be willing to take the unprecedented step of firing generals en masse if he didn’t like what they had to say. The Pentagon’s top brass, he alleged, “have been reduced to rubble … to a point where it’s embarrassing for our country.” Once he took charge, Trump continued, “they’ll probably be different generals.”

Set aside the spectacle of a major party’s presidential nominee bashing the military even though it’s one of the only institutions still respected by broad swaths of the public. Set aside that firing top military commanders simply because he didn’t like them goes beyond a president’s powers as commander in chief. And even set aside the idea that a businessman who admits to getting his information from “the shows” would be better suited to craft a war strategy than generals with access to highly classified information.

Here’s what Trump has revealed, again and again: He doesn’t actually know very much about ISIS — and he doesn’t know much about the nation’s generals.

War is what the military does. It’s not what the military wants.

In 1987, a promising young Army officer named David Petraeus finished his doctoral dissertation at Princeton. The title was “The American military and the lessons of Vietnam.” His main conclusion? The legacy of Vietnam meant that military commanders were more cautious about using force than the civilian officials who would order them into combat without doing any of the fighting themselves.

“Contrary to the stereotype of the military as hawks eager to employ military forces abroad, the post-Vietnam military generally have been quite circumspect in their approach to the use of force,” Petraeus, who would later become a famous four-star general in command of all US forces in Iraq, wrote in the dissertation. “[I]n no case since Vietnam has the military leadership proffered more aggressive recommendations than those of the most hawkish civilian advisers.”

Flash-forward almost 30 years, substitute “Iraq” for “Vietnam,” and generals chastened by one of the longest wars in American history have repeatedly made clear that they’re not eager to launch another one.

“It’s the opposite from what Trump believes — if anything, it’s the military that’s the most cautious,” said Evelyn Farkas, a former senior Pentagon official focused on Russia, Ukraine, and Eurasia. “It’s the military’s job to describe the risks and costs of any military operation, so they’ll naturally assume that things will last a long time, like in Iraq.”

Senior Pentagon officials have been unusually open about their desire to limit the US military role in the anti-ISIS fight.

In July 2013, Gen. Martin Dempsey, the then-chairman of the Joint Chiefs of Staff, sent a letter to Sens. John McCain of Arizona and Carl Levin of Michigan warning that the US had no easy military options in Syria and that some of the most common ideas tossed around in Washington — creating a no-fly zone, bombing key Syrian military installations — would be both costly and dangerous.

According to Dempsey, a no-fly zone would cost $500 million to set up and at least $1 billion a month to operate, and could result in US planes being downed. He said that establishing — and then protecting — humanitarian corridors designed to give Syrian civilians safe shelter from President Bashar al-Assad’s forces would require thousands of American ground troops. Ramping up efforts to train and arm rebels, he explained, risked US-provided weapons falling into terrorist hands and could leave American military advisers at risk of being attacked by ISIS sympathizers who had infiltrated insurgent ranks.

McCain, to put it mildly, didn’t like what he was hearing from the nation’s top military officer. “In my many years, I have seen a lot of military commanders overstate what is needed to conduct military action for one reason or another. But rarely have I seen an effort as disingenuous and exaggerated as what Gen. Dempsey proposed,” he said.

Trump, McCain, and other leading Republicans continue to call for the military to ramp up the anti-ISIS push, though they’re deliberately vague about the key question of whether large numbers of American combat troops should take part in the conflict. Many generals continue to urge caution.

“The folks in the military aren’t looking to have a long and expansive operation against the Islamic State that looks like Iraq,” Barno said. “There’s a lot of scar tissue that’s built up over the past 13 years, and serving generals know that it’s easier to get into a conflict than it is to get out of one.”

That isn’t simply because they worry that the ISIS fight could drag on interminably with no clear result. It’s because they worry that ISIS is the wrong enemy.

Let’s worry about Russia, not ISIS

For all of his bluster and tough talk about ISIS, Trump is remarkably sanguine about Russia and its autocratic leader, Vladimir Putin. Speaking at the same town hall where he likened American generals to “rubble,” Trump praised Putin for having a purported 82 percent approval rating (a number that comes solely from a pro-government think tank in Moscow) and for his “strong control” over Russia (which he’s attained by killing and exiling political opponents and journalists).

“The man has very strong control over a country,” Trump said. “It’s a very different system, and I don’t happen to like the system, but certainly in that system he’s been a leader. Far more than our president has been a leader.”

But it goes beyond just rhetoric: Trump has taken positions — endorsing Moscow’s military support for Assad in Syria, refusing to commit to defending NATO allies against a possible Russian invasion, and hinting that he’d be okay with letting Russia hold on to the parts of Ukraine it invaded and annexed — that are closely in line with the Russian leader’s long-held strategic goals.

Trump’s continued praise for Putin has been too much for leading Republicans like House Speaker Paul Ryan, whose spokesperson recently wrote that "Russia is a global menace led by a devious thug."

Ryan isn’t the only one who feels that way. Many of America’s top generals do, too — and openly say that Russia, not ISIS, is the biggest threat facing the US.

During his July 9 confirmation hearing, Dempsey’s successor, Marine Corps Gen. Joseph Dunford Jr. said “Russia presents the greatest threat to our national security” and “could pose an existential threat to the United States.” ISIS was fourth on his list, behind China and North Korea.

ISIS was even lower down the list of Dunford’s deputy, Air Force Gen. Paul Selva, who told lawmakers at the time that he “would put the threats to this nation in the following order: Russia, China, Iran, North Korea, and all of the organizations that have grown around ideology that was articulated by al-Qaeda.”

“Right now, [the Islamic State] does not present a clear and present threat to our homeland and to our nation,” Selva said, adding that Russia’s powerful armed forces could become an “existential threat to this country.”

That’s the second challenge to Trump’s calls for tougher measures against ISIS. The generals who would be charged with putting them in place would clearly rather focus on Russia. So what about simply putting in different generals?

Meet the new generals, not the same as the old generals

A President Trump would have no trouble — and would be well within his rights — relieving individual generals of command. President Obama did that to Gen. David McKiernan, once the top commander in Afghanistan, over concerns about his war strategy. Obama also relieved McKiernan’s successor, Gen. Stanley McChrystal, after he and his aides made disparaging remarks about the administration in a now-infamous Rolling Stone article. An array of other generals and admirals have been ousted for personal misconduct, such as improper sexual relationships.

But firing a large number of generals en masse would be an unprecedented move with the potential to do lasting damage to the military’s ability to function without being unduly influenced by domestic politics. Commanders could decide that it would be better for their careers to avoid telling civilian policymakers what they didn’t want to hear, even if the proposal in question seemed militarily, legally, or morally questionable. Others might simply quit in protest, robbing the Pentagon of some of its best and brightest.

Still, that’s exactly what Trump has been threatening to do. The Republican nominee regularly trashes decorated former officers — he slammed retired Marine Corps Gen. John Allen as a “failed general” after Allen backed Hillary Clinton — and talks of putting some of the former generals who have endorsed him into senior military posts.

Top on that list is retired Army Lt. Gen. Mike Flynn, who has stunned many of his former colleagues because of the vitriolic nature of his attacks on both Obama and Clinton. For instance, at the Republican convention in Cleveland this summer, Flynn said the US didn’t need a “reckless president who believes she is above the law” and clapped as the crowd began to chant, “Lock her up!” Flynn made it clear that he felt much the same way. “You’re damn right!” he said.

Flynn, once a respected intelligence officer, has also raised eyebrows among his former colleagues by co-writing a book that paints an apocalyptic picture of a future America conquered and ruled by Islamic militants.

“We’d live the way the unfortunate residents of the ‘caliphate’ or the oppressed citizens of the Islamic Republic of Iran live today, in a totalitarian state under the dictates of the most rigid version of Sharia,” he and co-author Michael Ledeen write.

“I’m totally convinced that, without a proper sense of urgency, we will be eventually defeated, dominated, and very likely destroyed” by the militants, Flynn and Ledeen write, adding that there’s “no doubt that they are dead set on taking us over and drinking our blood.”

That is the type of military thinker that Trump seems to want to put in a position of power if he wins in November. And that is what scares many retired officers the most.

“I don't think that Donald Trump will listen to the generals. He's said that he knows more about ISIS than the generals and more recently hinted that he would fire a number of the senior generals if he were elected president,” said retired Army Col. Peter Mansoor, a 26-year veteran who served as Petraeus’s executive officer in Iraq during the surge. “So much for getting the best military advice; what he will get in that case is a bunch of yes men (and women).”

Barno, the former top commander in Afghanistan, said Trump’s talk about stepping up the fight against ISIS — something many active-duty officers oppose — likely reflects the influence of Flynn and another retired officer, Lt. Gen. William Boykin. Boykin is a decorated former commander of the Army’s elite Delta Force who was later formally reprimanded by the Army for improperly disclosing classified material and who drew widespread condemnation for saying that a Muslim warlord worshiped “an idol.”

The takeaway is this: When Trump takes the stage Monday night for his first debate with Hillary Clinton, many top brass will listen in not just for clues about how he would fight ISIS, but also for signs of how he would run the biggest and most powerful military on the planet. They probably won’t like what they hear. And if Trump were to actually ask for their advice, he probably wouldn’t like what they said back.