It’s the season of anniversaries: My arrival in Vietnam, the 9/11 attacks, and now the one that’s still bleeding and will be hurting for a long time — the debacle in Afghanistan. There was ample warning about this one, but we failed to learn the lessons of British and Russian defeats in Afghanistan. It’s one thing to discuss abstract failures, but for soldiers the personal memories can be like the albatross around the neck of the Ancient Mariner — a horrible weight. It feels like just yesterday, but it’s been 54 years since the jet landed at Cam Ranh Bay. The door opened, letting in a blast of furnace heat and foul odors. The chaplain bounded up the steps, came in and stood in front of us. “Let us pray,” he intoned. It felt like the last rites.

Then I was out in the Forest of the Screaming Souls, as the Vietnamese call the Ia Drang Valley, site of the 7th Cavalry’s almost last stand in Vietnam. I knew this, but I was reassured by the presence of good men around me. Some of them had broken the law and crossed the border from Mexico for the express purpose of joining the U.S. Army and going to fight in Vietnam. So much they loved America, even if America has yet to accept them and ungratefully deports them. It’s a good thing, love of country. But I hope that never again will we send men to fight and die in wars that we cannot win.

Historians have documented that the U.S. did not have a strategy to win the Vietnam War. In his book, “Dereliction of Duty: Lyndon Johnson, Robert McNamara, the Joint Chiefs of Staff, and the Lies That Led to Vietnam”, Gen. H.R. McMaster, Donald Trump’s National Security Advisor, notes: “Clausewitz observed that ‘the political object is the goal, war is the means of reaching it, and means can never be considered in isolation from their purpose’.”

McMaster considers this to be a warning from history. As the war continued to grind along, “the application of means continued to escalate without a vision of how military action might actually achieve the goals of the war.” And so we lost the Vietnam War to the North Vietnamese, who indeed had a clear vision of purpose and the means to achieve it.

We failed to learn from our defeat in Vietnam, but failures to give or heed warnings are not just of the strategic kind. Sometimes they are tactical. Pulitzer Prize winner Lawrence Wright in “The Looming Tower: Al-Qaeda and the Road to 9/11” writes that two 9/11 hijackers, “Mihdar and Hazmi arrived nineteen months before 9/11. The FBI had all the authority it needed to investigate these men and learn what they were up to, but because the CIA failed to divulge the presence of two active members of al-Qaeda, the hijackers were free to develop their plot until it was too late to stop them.” And so, out of a misbegotten sense of rivalry between the FBI and CIA who weren’t talking to each other, we suffered the 9/11 attacks, the deaths of 3,000 people and the subsequent wars in Afghanistan and Iraq, instigated by the false belief in our omnipotence. This is not hindsight. Many observers in 2001 opposed the invasion of Afghanistan and the worst foreign policy mistake in U.S. history, the disastrous invasion of Iraq in 2003.

Another Pulitzer Prize winner, Thomas E. Ricks, writing in “Fiasco: The American Military Adventure in Iraq, notes: “The costs go well beyond that initial bill of blood and treasure. Iraq is likely to dominate American foreign policy for years … What happens in Iraq will influence the fate of the Middle East for generations to come, with a profound impact on our own national security.” We toppled the Saddam regime in Iraq but what happened after that? The “Arab Spring,” nice name, but not a positive development. The removal of despots in Tunisia, Libya, and Egypt only led to greater radicalization, the eternal civil war in Syria, the rise of ISIS, and the growth of Iranian influence.

Again, this is not hindsight. Many foresaw this and warned against it.

I would like to recognize John Foley, lieutenant colonel, Army (retired), who brought these books to my attention.

Joe Barrera, Ph.D., is the former director of the Ethnic Studies Program at UCCS. He teaches Southwest Studies and U.S. Military History.