Egyptian President Abdel Fattah al-Sissi, left, Saudi King Salman, center, and President Donald Trump at the Global Center for Combating Extremist Ideology, in Riyadh, Saudi Arabia.

Saudi Press Agency

It is not always clear what President Donald Trump is thinking on any particular issue.

On Iran, however, Trump appears to have decidedly hardline leanings.

He repeatedly called the nuclear deal “the worst deal ever negotiated” while on the campaign trail, where he also said Iran was “the number one terrorist state.”

While Trump and Secretary of State Rex Tillerson refrained from killing the deal this spring, the president has kept up the rhetorical pressure.

Most recently, during his trip to Saudi Arabia, Trump called for unity against Tehran and told assembled Arab leaders that, “For decades, Iran has fueled the fires of sectarian conflict and terror.” (Observers noted that assertion could also be made about his audience.)

“Until the Iranian regime is willing to be a partner for peace, all nations of conscience must work together to isolate Iran, deny it funding for terrorism, and pray for the day when the Iranian people have the just and righteous government they deserve,” Trump said.

In the White House and at the Pentagon and CIA, Trump has assembled a team that is well suited for pursuing that isolation – or turning to confrontation.

President Donald Trump meeting with his national-security team and other advisers.

White House handout

According to The Washington Post, active or retired military officials hold at least 10 of the 25 senior policy and leadership spots on Trump’s National Security Council – five times more than under Obama.

Some see the increase in military presence on the NSC as an important shift from the Obama years – one needed to properly address the protracted conflicts the US finds itself in.

Others, however, see such a concentration of military experience – potentially accentuated by a reduction in diplomatic staff on the NSC – as likely to result in a kind of myopia.

“It would take a remarkable individual to stand back from those experiences and think critically of them,” Andrew Bacevich, a retired Army colonel and Boston University history professor, told The Post. “It would be hard for them to consider that the path they had taken [in the wars] might have been a wrong one.”

President Donald Trump shakes hands with National Security Adviser Army Lt. Gen. H.R. McMaster at his Mar-a-Lago estate in Palm Beach, Florida, February 20, 2017.

REUTERS/Kevin Lamarque

Those officials, who draw much of their experience from Iraq in the late 2000s, may be limited in their worldview, Colin Kahl, a former Pentagon and White House official, told The Post. They could overestimate their ability to control events and end up provoking more conflict, Kahl said.

Army Lt. Gen. H.R. McMaster, Trump’s national-security adviser, believesIran was behind attacks on US troops in Iraq.The NSC’s senior director for the Middle East, Derek Harvey, is seen as an Iran hawk. And the NSC senior director for intelligence, Ezra Cohen-Watnick, has said he wants to use US spies to depose the Iranian government.

Across the Potomac River, Trump’s top man at the Pentagon is of similar extraction.

As a general, Secretary of Defense James Mattis commanded the 1st Marine Division during the 2003 invasion of Iraq and held other commands during operations there afterward.

While in Iraq and looking to retaliate for Iran-backed attacks on US personnel, Mattis devised plans for strikes in Iranian territory.

James Mattis, during his time as a Marine general.

US Marine Corps

Those plans were blocked by the Obama administration, but Mattis has maintained an aggressive stance toward the Iranian regime.

In late 2010, after taking over as chief of US Central Command, Mattis was asked by Obama what his priorities were.

“Iran, Iran, and Iran,” Mattis replied.

He has said he wouldn’t sign the Iranian nuclear deal (though he also says he considers it binding), and describes Tehran as the region’s most dangerous actor, calling it “more of a revolutionary movement than a country,” according to a New Yorker profile.

Mattis has also spoken dimly of what lies ahead for the US in the Middle East. “The future is going to be ghastly,” he said in 2016. “It is not going to be pleasant for any of us.”

Trump’s CIA also appears to be adopting an anti-Iran posture.

Under its new director, former Republican Rep. Mike Pompeo, who was a ardent foe of the Iran deal, the intelligence agency has made moves toward more aggressive spying and covert operations.

And, according to The New York Times, Pompeo has found a skilled leader for his Iran operations: Michael D’Andrea, an experienced intelligence officer known as the “Dark Prince” or “Ayatollah Mike.”

Rep. Mike Pompeo at his confirmation hearing to be the director of the CIA before the Senate (Select) Intelligence Committee on January 12, 2017.

Joe Raedle/Getty Images

D’Andrea, a Muslim convert, has gotten much of the credit for US efforts to weaken Al Qaeda.

Robert Eatinger, a former CIA lawyer who was involved in the agency’s drone program, told The Times it would not be “the wrong read” to see D’Andrea’s appointment as step toward a more hardline policy on Iran.

“He can run a very aggressive program, but very smartly,” Eatinger said.

In addition to Trump’s own bellicosity about Iran, there are signs the nationalist elements on his domestic-policy team are bleeding into the foreign-policy decision-making process, which – given their skepticism of international institutions and cooperation – could heighten the chance for conflict.

It’s also possible that the military figures in Trump’s national security apparatus could moderate the administration’s positions and spur more thoughtful consideration of foreign affairs.

Mattis himself has spoken of strong diplomacy as a preventative to war and has said military force can only be successful when it comes as part of a large political strategy.

“The conventional wisdom on this is probably wrong,” Peter Feaver, a Duke University professor who was a senior official in the second Bush administration, told The Post. “Empirically, the military is more reluctant to use force … but if force is used, then they want it to be used without restraint.”