MSNBC host Lawrence O'Donnell said on "The Last Word with Lawrence O'Donnell" that War Secretary Pete Hegseth's use of the phrase "we leave no man behind" was outdated, as he responded to remarks during a White House briefing about a recent U.S. military rescue operation.O’Donnell began by addressing Hegseth's statement directly and contrasting it with what he described as a more modern understanding of military service."That is, of course, the old school version of the idea back when only men flew American military planes," O'Donnell said.He pointed to how military language has evolved, noting that current leadership has adopted broader terminology.DEMOCRAT WHOSE PARENTS FLED IRAN MOVES TO OUST HEGSETHO'Donnell argued that the updated phrasing better reflects the inclusion of women in combat roles, claiming that General Dan Kaine's framing is more accurate."The general knows, unlike Pete Hegseth, that that could have been a woman they were trying to rescue," O'Donnell said. "It might be a woman the next time."HEGSETH DEFENDS TRUMP IRAN STRIKES, DEMANDS MEDIA ‘GET IT RIGHT’The MSNBC host then broadened his critique, challenging the idea that the U.S. military has consistently upheld the principle in practice."This 21st century notion that we leave no one behind ignores the 120,000 prisoners of war held by German and Japanese forces in World War II," O’Donnell said, noting they were "left behind" for years.He also referenced the Vietnam War, invoking the experience of the late Sen. John McCain.TRUMP SAYS IRAN’S SUCCESSION BENCH WIPED OUT AS ISRAELI STRIKE HITS LEADERSHIP DELIBERATIONS"In Vietnam, we left John McCain behind," O’Donnell said, recounting how McCain was captured and held as a prisoner of war for five years.O’Donnell connected that history to comments made by President Donald Trump during his first presidential campaign."When reminded that John McCain was a war hero, Donald Trump said he’s not a war hero," O’Donnell said, quoting Trump’s remark, "'I like people who weren’t captured.'"O'Donnell emphasized how modern rescue missions differ significantly from past conflicts.CLICK HERE FOR MORE COVERAGE OF MEDIA AND CULTURE"The idea of using 155 aircraft and hundreds of military personnel on an immediate rescue mission for a single person… was inconceivable in World War II or in Vietnam," he said.O’Donnell ultimately framed his criticism around what he sees as a disconnect between rhetoric and reality in military history and policy."The idea… ignores history," he said, arguing that the phrase has evolved beyond its original meaning and should reflect both modern service members and historical context.