President Donald Trump needs to step up and provide America with the leadership it needs — or else someone better suited should take over as commander in chief, according to retired Adm. William McRaven.

McRaven, who oversaw the Navy SEAL raid that killed al-Qaida leader Osama bin Laden in 2011, said the rhetoric and acts he witnessed at a change of command ceremony at Fort Bragg in North Carolina, and an annual gala for the Office of Strategic Services Society reminded him “why our future may be in peril.”

“What struck me was the stark contrast between the words and deeds heralded at those events — and the words and deeds emanating from the White House,” McRaven wrote in an op-ed Thursday published in the New York Times.

The change of command ceremony, between two generals McRaven said he served with for 20 years, portray solid character and understand the gravity of their responsibility leading their soldiers and had confidence in American values they have defended during their careers.

“They had faith that these values were worth sacrificing everything for — including, if necessary, their lives,” said McRaven, a SEAL who led Joint Special Operations Command before becoming the commander of U.S. Special Operations Command in 2011. He retired in 2014.

Similarly, the O.S.S. Society dinner featured films and testimonials highlighting the bravery of those who served in World War II, and celebrating the 75th anniversary of D-Day. Those servicemembers believed that “we were the good guys” and that the U.S. would fight to defend freedom.

America was needed, McRaven wrote, because who else would stand up to oppression and despotism?

Several other service members were also singled out during the O.S.S. Society dinner to honor their service, including Navy Chief Cryptologic Technician Shannon Kent, who was killed in January in a suicide bombing in Syria. Kent’s husband, who previously served as an Army Green Beret, was at the dinner to accept the Virginia Hall award posthumously awarded to Kent.

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“Like so many that came before her, she had answered the nation’s call and willingly put her life in harm’s way,” McRaven wrote.

Despite the focus on these honorable figures, McRaven noted he perceived some frustration and concern from those on both sides of the political spectrum that America is being threatened from within.

“As I stood on the parade field at Fort Bragg, one retired four-star general, grabbed my arm, shook me and shouted, ‘I don’t like the Democrats, but Trump is destroying the Republic!’” McRaven wrote.

“Those words echoed with me throughout the week,” he added.

According to McRaven, failing to appreciate what makes an organization great paves a path for the downfall of that organization. In essence, the U.S. is the most powerful nation due to the values that the U.S. promotes such as universal freedom and equality, he said.

In particular, he cited groups like the Kurds and the Afghans and questioned what would happen to them without the U.S. fighting the oppression they face. He then questioned how the U.S. could ever secure trust from allies if U.S. promises were empty, and what would inspire men and women to join the military to serve.

“If we are not the champions of the good and the right, then who will follow us?” McRaven wrote. “And if no one follows us — where will the world end up?”

McRaven accused Trump of not recognizing the significance of such values, and said now it is more necessary than ever to stand firm and espouse those values.

“If this president doesn’t demonstrate the leadership that America needs, both domestically and abroad, then it is time for a new person in the Oval Office — Republican, Democrat or independent — the sooner, the better,” McRaven wrote. “The fate of our Republic depends upon it.”

McRaven’s op-ed comes after the Trump administration withdrew U.S. troops from northern Syria earlier this month, prompting concerns that the move will reignite the Islamic State and giving the go-ahead to Turkey to launch an operation in the region against the Kurds who have fought alongside the U.S. to combat the Islamic State.

However, Turkey views Kurds with the Syrian Democratic Forces as a branch of a designated terrorist organization.

On Thursday U.S. Vice President Mike Pence announced a five-day cease fire in northern Syria following talks with Turkish President Recep Tayyip Erdogan in Ankara.

Analysts were quick to note that the agreement merely solidified Turkey’s objectives in northern Syria while calling on the Kurd’s to capitulate and cede territory to the Turks and their militia forces.

Secretary of Defense Mark Esper told reporters Friday that upon completion of the withdrawal of SDF forces from the 20 mile “safe zone” on its border “Turkey has committed to enacting a permanent cease fire.”

Esper said he called Turkish Minister of Defence Hulusi Akar on Friday and “reiterated the United States’ position that Turkey must adhere to the full terms of this agreement.”

The Trump administration first announced in December 2018 that ISIS had been “defeated” and that U.S. troops stationed in Syria would return home, a factor in the resignation of former Secretary of Defense Jim Mattis.