GERNIKA, Spain-On the northern coast of Spain, the blue ocean tides flow into coastal towns - their red clay roofs baking in the June sun, their painted fishing boats bobbing on the waves - as the green mountains spread out across the horizon like open arms.

It's easy here to drink wine, reclining around wooden tables and toasting your amigos who tell stories, pound their fists with passion on the white tablecloths, and laugh like it's their highest calling in life. It is easy here to love life.

It's hard to remember that more than 70 years ago, some of these towns were firebombed nearly out of existence.

On April 26, 1937, the Nazis - supported by the Spanish dictatorship - unhinged the locks on a most vicious Pandora's box: the blitzkrieg. Wanting to test a new form of warfare - the annihilation of cities through bombing - the planes flew over this town of several hundred people and dropped bombs for three straight hours.

Perhaps you've seen the Picasso painting of the event (which he titled "Guernica," the official Spanish spelling of the town's name): mothers with eyes askew hold their dead children; body parts scatter the canvas as a mad bull charges; empty hands clutch the air. In warfare, the surrealism of Picasso is reality.

Today, Gernika flourishes. But if you scratch the surface here in Europe, it's not long before you find that the ghosts of fascism and the Holocaust still haunt the landscape.

Traveling through Europe with other Americans as part of the Marshall Memorial Fellowship, I've encountered a Europe still tangled in its own history. Neo-Nazis are a presence in many countries, while displaying the swastika is illegal in others.

Tilting threateningly toward xenophobia, a significant trend toward nationalism is spreading as native Europeans react to large numbers of Muslim immigrants from northern Africa.

Perhaps the reasons are understandable. As William Faulkner, the sublime Mississippi gentleman of Southern literature, wrote: "The past is never dead. It's not even past."

Yet when the past includes the madness of dictatorships and concentration camps, it's important - vitally - to understand what caused the violence of old. Ratko Mladic, the Bosnian Serb accused of war crimes, may have been arrested, but it takes more than one man to make a genocide.

To understand why, imagine that the room you are sitting in now suddenly caught fire.

You'd rush out and call for help. Immediately.

We all would.

Right?

Years ago, a social experiment explored the power of conformity. Volunteers were gathered and asked to fill out forms to prepare for an upcoming experiment. As they sat alone - one at a time - in a room circling multiple-choice answers, the experiment had already begun, though they didn't know it.

From the air vent in the room came smoke. Thick and thicker. It was a trick; there was no fire, but the volunteers, who moments ago had been filling out forms, did not know that.

Hidden, the researchers timed how long it took before the volunteers - thinking the building was on fire - put down their pencils, rushed up from their chairs and ran to safety.

Thankfully, nearly every volunteer left the room within 60 seconds.

That is, until the researchers changed the experiment.

One by one, new volunteers were placed in a room to fill out forms. Yet sitting next to them were actors, paid to pretend to be fellow volunteers. As the smoke seeped into the room, they remained in their chairs, heads down, pencils moving.

The smoke got thicker. The researchers timed how long it took for the one volunteer - while the others acted as if nothing was wrong - to leave the room and call for help.

The results were shocking: Nearly 90 percent of all volunteers stayed in the room even though it seemed the building was on fire. Stayed even as the smoke got so thick they could barely see their hands in front of their face.

The world was burning, but since no one else seemed to notice, they ignored their own mind, conscience and logic and stayed in the seat.

This is the dangerous power of conformity.

This is the dangerous power of crowds and peer pressure.

This is the dangerous power of humans to ignore their own consciences, to follow orders and watch as the world burns. Violence happens not because of a single Hitler, but because of the everyday people who stand by and watch.

In my life, I've remained seated when I should have gotten up. I've kept silent when I should have spoken. I've watched when I should have run. I've left many things undone.

Yet the people in northern Spain reminded me that every day we face a choice. Each day is like walking into a room, and if we see smoke, we must run, no matter what the world around us does or does not do.

And if we walk into the room and there is no smoke or fire, then we must open our arms to the life before us. We must sit down, stretch our legs, uncork a bottle from the shelf and break bread with friends.

For in the Spanish town by the sea, there are some things even the hottest fires cannot burn down.

David Cook can be reached at davidcook@blumail.org.