Washington — Admiral Mike Mullen, the former chairman of the Joint Chiefs of Staff, said Sunday that a reported episode contained in new books about former President Trump and his final months in the White House that described efforts for him to remain in power is “incredibly disturbing” and demonstrates the “chaotic environment” of the Trump administration.

Several of the recent books published about Mr. Trump, as well as an article in the New Yorker, detailed the concerns from General Mark Milley, the current chairman of the Joint Chiefs of Staff, that the former president would use the military to stage a coup to deny President Biden the presidency or launch a strike on Iranian interests as a way to remain in power.

In an interview with “Face the Nation,” Mullen said he understands the reporting about the final weeks of the Trump administration to be “pretty accurate,” and described the time after the presidential election as “chaotic.”

“The two threats that you talked about, the external one, and whether or not we would commence some kind of combat or conflict with Iran, and then the internal one in terms of where it might go, particularly with respect to how the military would be used by President Trump to somehow validate that the election actually was a fraud and keep the president in power, I think that’s all very accurate and obviously incredibly disturbing, literally in every respect,” he told “Face the Nation.”

Mr. Trump spent the weeks after the presidential election spreading baseless claims the contest was rife with widespread voter fraud and alleging the election was rigged against him. But the former president lost all legal battles filed in an effort to reverse the outcome of the presidential elections in several key battleground states, and federal cyber agencies declared the 2020 election to be the most secure in U.S. history.

Mr. Trump’s baseless claims about the 2020 election culminated in the January 6 assault on the U.S. Capitol, when a mob of his supporters breached the building in an attempt to stop Congress from re-affirming Mr. Biden’s victory.

According to one book, “I Alone Can Fix It: Donald Trump’s Catastrophic Final Year,” written by a pair of Washington Post reporters, Milley compared the former president’s rhetoric to Adolf Hitler’s and had “a stomach-churning” feeling listening to Mr. Trump’s false allegations of election fraud.

Mullen said top military leaders like himself and Milley typically engage in “very tough, heated debates” with a president but carry out with a decision made by the commander-in-chief. But with regards to Mr. Trump, Milley acted correctly in pushing back, Mullen said.

“I think General Milley and others who’ve served over the last four years would tell you it’s been a very chaotic environment, very difficult to predict what was going to happen from day to day, and great concern with respect to the possibility of some of the orders that might come the military’s way,” he said. “General Milley, I thought, really did the right thing on both fronts, quite frankly. I don’t think he was alone with respect to Iran. But I think on the internal potential for a coup, really, really stood up, did the right thing, and I think made the case that he was the right officer to have in the right job at the right time in a very, very difficult, stunning and unprecedented situation.”

Mullen said that if Mr. Trump attempted to use the U.S. military to remain in power, Milley and other military leaders would have been forced to resign.

“That rubs up or actually it’s contrary to the Constitution, which is what the military serves, as opposed to the president, and could be seen as an illegal, immoral or unethical order, in which case, you know, General Milley and the rest of the military leadership, the other four stars, in my view, would be would be required to either resist or if they’re unable to resist, resign,” he said.

While Mullen not only had concerns about the military being politicized during the Trump administration, he said he continues to harbor those fears today.

“The political environment is so intense and so divided and we need to work hard to make sure the military doesn’t become part of what is politicized in this country,” he said.