In April 1975 two related events occurred. First, Saigon fell to the North Vietnamese. Americans watched with dismay as the final helicopters evacuated U.S. citizens and U.S. supporters from the roof of the American embassy. Then, only a few weeks later, the Cambodian capital, Phnom Penh fell to the Khmer Rouge – an event that received very little coverage. While those left behind in South Vietnam suffered numerous indignities and many were imprisoned, it was ultimately the Cambodian people that paid the price for the Vietnamese war that lingered on for over two decades.

Once the Khmer Rouge took power they instituted policies that resulted in the genocide of 2,000,000 Cambodians. Events in Cambodia still received almost no news coverage. While the U.S. government was well aware of what was going on, it had no interest in doing anything to stop the murders. America was a war weary country, and its leaders had no intention of getting involved, once again, in Southeast Asia. The extent of horror in Cambodia only came to light with the screening of the film “The Killing Fields”, in 1981. By then, even if anyone had cared to act, the Khmer Rouge had been defeated.

Fast-forward several decades … In April 2011 the Syrian uprising began against the rule of Bashar Assad. After a period of time, when the Syrian regime had killed hundreds (if not thousands) of unarmed demonstrators, the protestors picked up arms and began fighting back. To date, nearly 200,000 Syrians have died (most of them civilians), and over 4 million Syrians have become refugees.

On December 11th 2011, the last U.S. combat troops crossed over the Kuwait border coming from Iraq. America’s long war in Iraq was officially over. At the same time, the war in Afghanistan continued, though American involvement was rapidly winding down. After more than a decade at war, America was again war weary. A feeling that was exacerbated by the bi-partisan agreement that little had been accomplished in this difficult decade of war.

Both of these sets of events – though separated by over 35 years – are linked. The deaths in Cambodia and the deaths in Syria are both the unintended consequence of American actions, which occurred in both cases after America became tired of its previous military involvements and withdrew. This is in no way to suggest that America is directly to blame for these tragic events – as it was not Americans doing the killing. On the other hand, today there are those who still blame F.D.R. for not doing enough to save the Jews during Holocaust. Despite the fact that Hitler’s “war against the Jews” was without question not an unintended consequence of U.S. policy. The U.S. was fighting an all out war against Hitler. In the case of both Cambodia and the case of Syria it was America’s actions that paved the way for the massacres that were to come.

In Cambodia it was American involvement in the Vietnam War, and its extension to Cambodia, that undermined the relatively stable, neutral Cambodian government. The Civil War that ensued in Cambodia led to the victory of Khmer Rouge over the government of Lon Nol, which the U.S. abandoned, as it had discarded the government of South Vietnam. When the massacres started occurring in Cambodia it was in everyone’s interest to look the other way. No one on the political Left would dare to voice concern. After all, the Left had pushed so hard for U.S. withdrawal they were not about to protest the genocide taking place in Cambodia. The Right was only interested in American “interests” and fighting communism.

American responsibility for events is Syria is more indirect. The U.S. certainly did not start the revolt. Furthermore, it’s clearly Russia and Iran who bear the responsibilities for aiding Bashar Assad and his murderous regime. However, it was the American invasion of Iraq that fueled the Shia-Sunni split in the Arab world that had been on a low burn for centuries. This split has now spilled over to all areas of the Middle East – especially Syria. It also helped drive what started as demonstrations to bring more democratic rule to Syria,  into a homicidal civil war, that clearly borders on genocide.

There is one major difference between events in Cambodia from what is happening in Syria. The world was largely unaware of tragedies in Cambodia. Even if there had been a will to stop the genocide, it would have taken the intervention of the hundreds of thousands of American ground troops going half way around the world to bring it to a stop. In Syria the solution has always been easier – i.e. establish a no-fly zone over large parts of Syria. This would not end the killing completely, but it would save thousands of lives, and it can be done without moving a single soldier. The U.S. has sufficient aircraft in the region to easily enforce a no-fly zone. America successfully enforced a no-fly zone on Saddam Hussein for over a decade, without losing a single pilot to hostile fire.

We can say “Never Again” as many times as we want. Though if the premeditated murder of civilians is allowed to persist year-after-year, without being stopped, it is clear that the world is only paying lip service to remembering the Holocaust. If this degree of barbarism can happen in Syria, in the full view of the world, then such atrocity can happen anywhere.

This is a rather unique moment in history, a moment when a U.S. strategic interest – (e.g. weakening the growing regional power of Iran and Russia), and humanitarian interest – (e.g. ending the killings) are aligned. Yet, the U.S. has done little. The U.S. is the only force, other than Israel, (who cannot for obvious reasons) who can stop the killings. Allowing the Syrians to continue makes the U.S. an accomplice.

I know the American people are war weary. I also know that President Obama is committed not to involve the U.S. in any foreign wars. However, being a great power comes with great responsibilities. Long ago, Edmund Burke said it most succinctly: “The only thing necessary for the triumph of evil is for good men to do nothing.