Does historical truth matter? Should we tell the truth even if it hurts? Or should we set it aside to serve our present-day purposes?
I've been wondering about those questions ever since Israeli commandos attacked a Turkish aid flotilla bound for Gaza, killing nine people.
U.S. officials worried that the raid would further strain our delicate relations with Turkey, which has been a crucial American ally for many years. Turkey provides airspace for our military exercises, bases for supplying our troops, and - most important - a bulwark against terrorism and extremism in the Middle East.
And, nearly a century ago, Turkey committed genocide.
There, I said it. So did Barack Obama, when he was running for president. But after he came to power, Obama changed his tune.
Lest he alienate the Turkish government, Obama has refrained from using the term genocide to describe Turkey's massacre of roughly 1.5 million Armenians in 1915.
But I think he should. Turkey did commit genocide, as every credible historian acknowledges. By avoiding the term, we will make it easier for other regimes to engage in genocide. And it will be harder for us and the rest of the world to hold them to account.
That seems to have been Obama's own position back in January 2008, when he promised to recognize the Armenian genocide if elected president. "The Armenian genocide is not an allegation, a personal opinion, or a point of view, but rather a widely documented fact," Obama declared. "An official policy that calls on diplomats to distort the historical facts is an untenable policy."
But earlier this spring, when a House committee passed a resolution condemning the genocide, White House officials lobbied lawmakers to reject it. Obama called Turkish President Abdullah Gul to emphasize his opposition to the measure, while Secretary of State Hillary Rodham Clinton - who also supported acknowledging the genocide during her presidential campaign - pledged that the administration would "work very hard" to prevent the bill from reaching a vote by the full House.
The same thing happened in 2007, when the Bush administration persuaded House Speaker Nancy Pelosi to block a vote on a genocide resolution. Its reason? We needed Turkey to help us win the global "war on terror."
We needed Turkey in 2000, too, when Bill Clinton squelched a similar resolution on the grounds that Turkish military bases were helping us patrol the no-fly zone over northern Iraq. And we needed Turkey in 1985 and 1987, when it provided posts for monitoring the Soviet Union - and two other genocide resolutions went down to defeat.
Does anybody see a pattern here? The United States will always need Turkey for one reason or another. But we also need to tell the truth about the Armenian genocide, lest we sacrifice our credibility on the world stage.
More than 20 countries - including France, Canada, Switzerland, and Sweden - have recognized the Armenian genocide. So have 29,000 Turks who risked government imprisonment and harassment by signing a petition apologizing for the episode last year.
The United States has officially condemned Iranian President Mahmoud Ahmadinejad for denying the Holocaust. How can we tout Turkey as a buffer against Iranian nuclear ambitions while turning a blind eye to Turkey's own genocide denial?
Or consider the situation in Darfur, which the Obama administration has rightly described as a genocide. Why do Sudanese murders in Darfur meet the standard, but Turkish massacres of Armenians don't? When we refrain from condemning one genocide, we make it harder to sustain the case against others.
To understand why, consider the words of the leader of the most notorious genocide in history, Adolf Hitler. In 1939, Hitler assured his military advisers that his planned "depopulation" of Poland would be quickly forgotten. "Who, after all," Hitler asked, "speaks today of the annihilation of the Armenians?"
We are. And we must. Even in the wake of the Gaza raid - and even at the cost of our friendship with Turkey - we need to tell the truth about every genocide, past as well as present. Anything less will set the stage for more.