This is Hidden Brain, I'm Shankar Vedantam.

Early in the morning on August 17, 1999, an earthquake struck northwestern Turkey.

It was the first of two earthquakes that would devastate that nation and parts of Greece.

Whole cities were reduced to rubble. Thousands of people were killed and hundreds of thousands were left homeless.

I made the destruction, however, something extraordinary happened.

Turkish rescue workers saved a Greek child from the wreckage of a building.

A Greek man offered to donate a kidney to someone in Turkey.

And the Greek Foreign Minister, George Papandreo, called on his fellow Greeks to offer aid.

I heard the news and the media immediately asked me, have you sent a statement?

And I said, you know, I sent a statement, but I want to say something more.

Why don't we help the Turks? Why don't we give blood?

What made this remarkable is that Greece and Turkey have long had a rocky relationship,

marked by periods of open warfare and animosity.

But George Papandreo saw an opportunity for rapprochement between the two nations.

I felt this was a real issue, but it was also a political act.

The idea of blood, of course, has a much deeper symbolism.

The interesting thing which I hadn't expected was there was an outpour of help.

In the weeks that followed, the blood drive intervention and other aid efforts

transformed the way many Greeks and Turks saw each other.

They began to view each other not as enemies, but as fellow victims of a terrible disaster.

Very quickly, this sentiment spilled over into new domains.

So then all of a sudden you saw things coming out which, you know, we would never expected.

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