Barack Obama has an exquisite sense of timing with things communist.

In March, he caught a ballgame in Havana with Raul Castro, where the national pastime since 1959 has been less baseball than bean-balling dissidents and destroying a beautiful country 90 miles south of Florida. As Barack and Raul bantered, Belgium burned while ISIS claimed victory in another terror attack -- the very ISIS enabled by Obama’s outrageously bad decision to prematurely pull U.S. troops from Iraq.

In September 2009, Barack went to Poland where, stunningly, he cancelled plans for a joint U.S. missile-shield with a former Soviet Bloc country that has been one of our closest post-Cold War allies. This was merely one of Obama’s craven pro-Putin accommodations. He did it -- as every Pole noticed -- on the 70th anniversary of the date (September 17, 1939) that Stalin’s Red Army invaded Poland in compliance with the Hitler-Stalin Pact that started World War II and launched a 50-year totalitarian occupation of Poland.

And now, a week before Memorial Day, when Americans honor (among others) the 58,000 boys who died in Vietnam, Obama flew to Hanoi to make amends and “move on” (as John Kerry put it) with another communist regime. There, our president discussed the glories of lifting the long-held U.S. arms embargo against Vietnam.

It is truly a new era, folks, with our President of Fundamental Transformation lifting embargos on old communist enemies from the Western Hemisphere to Southeast Asia.

There were those of us who warned incessantly of the pitfalls of electing our first Red-Diaper Baby president, the product of pro-communist parents and a literal card-carrying member of Communist Party USA who mentored him. But we were told by liberals that none of this mattered. Nah, this was mere McCarthyite red-baiting, a witch-hunt smear against this impressive “progressive” president.

And alas, here we are: we are treated this week to the image of a smiling Obama shaking hands in Hanoi with the president of communist Vietnam in front of a large bust of a grinning Ho Chi Minh poised in front of a big red flag with a star, outdone only by the image of Obama standing proudly, head up, ramrod straight, with the communist leadership in front of a giant mural of Che Guevara in Havana in March.

What’s next? A beer at the DMZ with Kim Jong-un?

Obama’s Vietnam tour is troubling in so many ways. Where does one start?

If I may, I would like to suggest some reading, like when Obama’s pal Hugo Chavez -- forerunner of the Venezuelan socialist-Marxist marvel -- eagerly offered our new president a book back in April 2009. I recommend it to anyone outraged (or, even more so, to those not outraged) by Barack’s tour in Vietnam. This is a teachable moment on the history of the Vietnam conflict, and perhaps how all of this might have been avoided 50 years ago.

The book is a superb work by author Geoffrey Shaw, The Lost Mandate of Heaven: The American Betrayal of Ngo Dinh Diem, President of Vietnam (Ignatius Press).

If you do not know the full story of Diem, and just how badly the Kennedy administration blew it by allowing for his assassination, then you need to read this book. The Kennedy team sanctioned the November 2, 1963 coup d’etat against Diem. Ironically, Diem was assassinated the same month that Kennedy himself was assassinated, and both men were strong anti-communists. The deaths of each man allowed for successors who wildly escalated the violence in Vietnam. One more irony: Kennedy was, of course, America’s first and still-only Catholic president. Diem himself was not merely Roman Catholic but a remarkably devout Christian who would have preferred a monastery to the leadership of Vietnam. He was better suited for the priesthood than presidency. Quite profoundly, Diem was at Mass the morning he was killed. That was typical, as he was up for Mass at 6:30 every morning. This particularly fateful day happened to be All Souls’ Day, and he was seized on church grounds and killed. The United States either approved or set up (or at least sanctioned, as scholars still debate this) the assassination.

Diem was not only a devout man, but a man of principle and character and an unusually honorable politician as well as patriot, despite how he was vilified by detractors in the United States. The communists in Vietnam knew that the respect that he rightly earned from the populace was their greatest obstacle. After his killing, everything would spin out of control.

Shaw’s book sickeningly chronicles the slow, steady abandonment, demonization, and betrayal of Diem by certain elements in the United States, thus leading to his martyrdom. And yes, many Vietnamese consider it martyrdom. To be sure, Diem had his supporters, from the likes of William Colby and Dean Rusk to two excellent ambassadors, Frederick Nolting in the United States and Robert Thompson in Britain. Nonetheless, they were no match for a relentless anti-Diem campaign led by the New York Times (reporters like David Halberstam) and most egregiously by Kennedy adviser and esteemed liberal “wise man” Averell Harriman. It was Harriman who led the cabal to do in Diem, and he pulled it off.

“The actions of these men led to Diem’s murder,” Shaw grimly concludes. “And with his death, nine and a half years of careful work and partnership between the United States and South Vietnam was undone. Within a few weeks, any hope of a successful outcome in Vietnam -- that is, of a free and democratic country friendly toward the United States -- was extinguished. Truly, in order to solve a problem that did not exist, the Kennedy administration created a problem that could not be solved.”

Barack Obama, inculcated as he was by the family and mentors he had, and educated as he was at places like Occidental and Columbia University, would not have learned these lessons of Vietnam. And the students brainwashed in our academic insane asylums are surely not learning any of this today. Do yourself a favor, and your kids or grandkids a favor, and get them Geoffrey Shaw’s book on the betrayal of Diem. You might even buy an extra copy to be sent to the White House.

Ironically, Barack Obama was able to blithely stand by Ho Chi Minh in May 2016 because the Kennedy administration refused to stand by Ngo Dinh Diem in November 1963. His ignorance, like the Kennedy administration’s, and like ours, continues to cause enormous damage.

Dr. Paul Kengor is professor of political science at Grove City College. His latest book is Takedown: From Communists to Progressives, How the Left Has Sabotaged Family and Marriage. His other books include The Communist: Frank Marshall Davis, The Untold Story of Barack Obama’s Mentor and Dupes: How America’s Adversaries Have Manipulated Progressives for a Century.