Obama stood at a podium with the epicenter of the blast, the Genbaku Domu, in the background and said that he had "come to mourn the dead." While Obama mourned, there was one thing he did not do: apologize.
He said that "death came from the sky." No mention of why. Or who was responsible, as if it were a natural disaster rather than a crime perpetrated by actual people. Obama was either unwilling or unable to confront the truth and make amends.
Here's what he could have said to try to do so:
Seventy-one years ago, on a bright cloudless morning, an American warplane unleashed the most horrific and inhuman weapon ever invented, immediately imperiling the survival of the entire human species. This act of terrorism was the ultimate crime: a crime of mass murder, a crime of war, and a crime against humanity.
The victims, those who died incinerated in a flash, and those who died slowly and painfully over years from chemical poisoning, were never able to see justice served. Sadly, there is no way the criminals who carried out this heinous and barbaric act will ever face justice for their crimes.
I cannot change that. But, there is one thing I can do as the leader of the nation in whose name the bombing of Hiroshima was carried out: I can tell you, residents of Hiroshima and the rest of Japan, that I am sorry. I am sorry on behalf of my government and my country. I wish an American President would have come earlier and said this. This apology is decades overdue. It is a small and symbolic act, but it is necessary as a first step for true reconciliation.
A nuclear bomb should have never been dropped on Hiroshima. The most important goal of mankind should be to ensure that no nuclear bomb is ever dropped again. Anywhere in the world. Ever.
It would be easy to stand here and tell you that there are reasons why the American military and political officials chose to use a nuclear bomb. I could say it served a greater good of saving lives that would have been lost if the war had continued. I could say it was a decision made by people who were dealing with the pressure and horrors of fighting a war. But that would not be the truth. Those would be empty rationalizations. There is no justification for the bomb. Period.
The truth is that by August 6, 1945 Japan was defeated and had been seeking a conditional surrender for months. And American war planners knew this. They knew it because they had cracked the Japanese code and were intercepting their messages. 
Japan was willing to surrender under the condition that their Emperor, who was seen as a God among the Japanese people, be allowed to maintain his throne and not be prosecuted for war crimes. The Emperor himself called for "a plan to end the war" six weeks before the fateful day.  After so much unspeakable death and destruction, this reasonable offer should have been met with ecstatic celebration and relief.
Instead, U.S. officials disregarded it. They decided that it was necessary not just to defeat Japan, but to leave them utterly humiliated and disgraced. They wanted to demonstrate to their public that they could force another country to lay prostrate in front of them in complete submission. This is the mindset of terrorists, torturers, and sadists.
The United States joined with China and Great Britain to issue the Potsdam Declaration on July 26, in which they called on Japan "to proclaim now the unconditional surrender of all Japanese armed forces." These were terms they understood Japan could not accept.
Unfortunately, the use of the atomic bomb had become inevitable after the massive investment of time and treasure represented by the Manhattan Project. Military planners worried about "the possibility that after spending huge amounts of money ... the bomb would be a dud. They could easily imagine being grilled mercilessly by hostile members of Congress."
Historian and former Nuclear Regulatory Commission employee J. Samuel Walker confirmed that aside from "shortening the war and saving American lives, Truman wanted to justify the expense and effort required to build the atomic bombs."
That financial considerations and a self-interested desire for bureaucrats to validate themselves and protect their careers could lead to the single most destructive and cruel act in history is an abomination. It is a deep offense to the idea that people are innately moral, and it makes us ask how in a democratic society we can vest people with the authority to make decisions of such profound impact secretly and without accountability?
Walker notes that another consideration for using the bomb on Hiroshima was to put fear into the leaders of the Soviet Union and make them "more amenable to American wishes." Just six weeks earlier the UN Charter had been established. It included the demand that "all members shall refrain in their international relations from the threat or use of force" against other states. The drafters of the treaty could never have imagined such an unconscionable violation of their words so soon after the monumental pact had been written.
As horrific as the nuclear bombing of Hiroshima was, it did not occur in a vacuum. What no one in mainstream American political discourse has so far been able to admit is that not only was there no justification for the bomb, there was little justification for the war against Japan in the first place.
The war was the result of the notion, which first emanated from the Council on Foreign Relations in 1941, that the U.S.'s "national interest" called for a "Grand Area" that consisted of the Western hemisphere, the British Empire and the Far East, while assuming the majority of Europe would be controlled by Nazi Germany. This was translated into a policy that demanded a military confrontation with Japan for control of the Far East. 
A pillar in this policy was an economic embargo against Japan. Cut off from imports and raw materials from the United States and Great Britain, Japan grew desperate and subsequently sought to expand its Empire. Japan saw itself in need of a sphere of influence involving the same areas in the Far East as the United States.
The U.S. had several options to avoid war. For one, they could develop a program of agricultural and economic self-sufficiency which would allow them to insulate themselves from dependence on colonial powers, as well as allow them to steer clear of unpredictable and potentially hostile regions of the world.
But for businessmen who wanted to maintain control over the direction of the economy and keep their own fortunes growing at a limitless pace, this was a nonstarter. Instead, they were dedicated to challenging Japan. Hence, the embargo and the buildup for an inevitable military confrontation over Eastern Asia.
This is the background to Pearl Harbor. Japan was obviously not justified for attacking sovereign American territory in a blatant act of aggression. But we cannot pretend that it was not predictable or logical from their point of view.
Japan felt itself backed into a corner by the embargo. They felt they needed to expand further into Asia. They believed that if they did so, the U.S. military would have attacked them. They were right.
Both countries should have worked together to recognize each other's perceived interests, deescalate, and achieve a mutually acceptable compromise. It is the ability to understand one's perceived adversary as a rational counterpart, rather than an evil and irrational enemy, that separates humans from beasts. If we are not able to use this ability, we are no better than a predator seeking his prey.
The nuclear bombing of Hiroshima did not need to happen. But the bombing that took place on this site was just a symptom of the war it was part of. War will necessarily produce horrific crimes, some of which are unimaginable at the time they happen. As horrific as the nuclear bomb was, 70 years of technological advancements have made not just the destruction of an entire city, but of an entire country or continent within the realm of possibility.
We need to eliminate nuclear weapons from the earth. But that is not enough. Chemical weapons like napalm, Agent Orange, depleted uranium, and white phosphorous; biological weapons like Dengue bacteria and germ bombs; and conventional weapons like cluster bombs, pineapple bomblets, butterfly bombs and land mines are just some of the savage weapons used by the U.S. military alone in the years since the close of World War II to kill and maim millions of people. Many other countries possess similar weapons of mass destruction and have the capacity to do the same.
We need to eliminate war. All war. Forever. War is evil, plain and simple. We cannot undo the actions of the past. But we can let them guide us to a better world where we don't repeat the horrors that the people of Hiroshima suffered here 71 years ago. That will be the only way to prevent the victims from having died in vain.
 Zinn, Howard. A People's History of the United States: 1492-Present. New York: HarperCollins, 2003. pp. 423.
 U.S. Strategic Bombing Survey: The Effects of the Atomic Bombings of Hiroshima and Nagasaki, June 19, 1946. President's Secretary's File, Truman Papers. http://www.trumanlibrary.org/whistlestop/study_collections/bomb/large/documents/index.php?pagenumber=33&documentid=65&documentdate=1946-06-19&studycollectionid=abomb&groupid=
 Shoup, Laurence H. and William Minter. Imperial Brain Trust: The Council on Foreign Relations & United States Foreign Policy. Lincoln, NE: Authors Choice Press, 2004.
Matt Peppe writes about politics, U.S. foreign policy and Latin America on his blog. You can follow him on twitter.