The wails of air-raid sirens echo off the ritzy shops and the grand modernista facades of the apartment buildings lining the Plaça Catalunya, as thousands of "bombs" explode among the civilians gathered in the square. People fall to the ground in silence, while others stand with raised fists, defiantly repeating the chant they've been shouting for weeks: "No a la guerra!"

These so-called "bombs" aren't real, but some 50,000 black balloons exploding in a visceral protest against the war in Iraq. The display is just one of many war protests taking place on this last weekend of March in Barcelona, a city that seems now in a constant state of protest.

We had scheduled this trip to Barcelona weeks before the cruise missiles started targeting presidential palaces – and gone through with it over the protests of worried relatives and colleagues who said it was crazy to board an Airbus in wartime. For our part, we were sorry to miss the first major anti-war rally in our hometown of Boston, called for the same weekend, which drew tens of thousands to Boston Common – one of the main venues for protests in the Vietnam war era. On our way in from the airport, we asked our taxi driver where the anti-war protests would be. He laughed, and said, "Everywhere."

And so it is. On nearly every block in every neighborhood, sheets hang from the windows of businesses and residences alike, spray-painted black and red with slogans: "No Sangre Por Petroleo" (No Blood for Oil), "Bush No! Guerra No! Saddam No!" and "Alturem La Guerra" ("Stop the War" in Catalan). There are anti-war emblems pinned to the lapels of wool overcoats and anti-war stickers plastered on the side of trendy leather handbags. American fast food joints which are empty except for a few die-hards ignoring the calls for boicots of American products. No less than nine policemen are stationed around a McDonald's and an abutting Kentucky Friend Chicken.

You can't walk down the street, order a beer, or shop for a hat without being constantly bombarded by reminders of the very real bombs falling on Baghdad, as close to Barcelona as Denver is to Boston. Flyers around town advertise new manifestacions for the coming days: April 2, April 7, April 10, April 15 and so on. This is not a single march but a weeks-long marathon of anti-war sentiment.

World Capital of Peace

Known for its colorful street life and whimsical Gaudi buildings, Barcelona has been a center of the Spanish Left for decades – the hangout of choice for writers, communists, artists, acrobats, and anarchists. The city was the last stronghold of the Republican army during the Spanish Civil War, and, along with the Basque country, suffered most from Franco's tanks and bombs. In his Homage to Catalonia, George Orwell wrote, "I had dropped more or less by chance into the only community of any size in Western Europe where political consciousness and disbelief in capitalism were more normal than their opposites."

Not surprisingly, the city has now emerged as the eye of the storm of peace protests in Spain, already the country with the strongest anti-war sentiment in Europe. Even while protests in Paris and Berlin have reportedly begun to sputter, La Vanguardia newspaper loudly proclaims Barcelona the new capital mundial de paz, the world capital of peace. 400,000 people marched peacefully in the streets the weekend after the start of the war, on a day that London fielded half that number, and New York only a quarter.

Unlike protests in the U.S., where 70 percent support the war, people here don't need to convince their neighbors. In Spain, 92.4 percent of the people are against the war. The Spaniards are instead banding together in sorrow and outrage to send a message to the rest of the world and their own embattled president. Even the normally apolitical kids at the discos are talking war. "Bush is a bully," says Jaime, whom we meet on the way to a club downtown. He seems surprised to learn that many Americans are also against Bush. Like others in his country, he has no idea that millions of Americans feel just as ignored by George Bush as the Spanish populace does by Aznar. "Everyone knows Aznar is finished in the next election," says Jaime, "for the sole reason of the war. No one knows yet who the next president will be, but it won't be him."

A Spectacle of Protest

What is remarkable about the protests here isn't just their size and regularity, but the sheer creativity they exhibit. In addition to the fake bombing in the Plaça, an artist's colony has been set up in front City Hall in the heart of the Gothic quarter. There are dozens of paintings and conceptual art exhibits depicting such scenes as an American soldier smiling while standing on an Iraqi skull, and President George Bush's head on the body of a pig. The camp was set up when the bombing began and was intended to last a few days but now seems to have become a permanent feature.

On the day of the balloon "bombing," a huge Concert For Peace draws 35,000 to hear dozens of musicians and speakers, as well as on-stage skits broadcast on jumbo-trons, and group sing-a-longs to more Beatles songs – "All You Need is Love," and "Give Peace a Chance," all translated into Catalan. In the midst of the music and performances, a young Spanish acrobat is sent aloft on a trapeze attached to a giant helium-filled globe covered with multi-lingual slogans for peace, her flowing dress streaming in the wind as she flips and pirouettes dozens of meters above the swaying crowd. At the same time, a nearby performance troop whose name translates as "Vermin of the Sewer" leads dozens of people to strip naked and bare their bodies for peace.

Along the Ramblas – the downtown pedestrian thoroughfare full of shops and street performers – half a dozen booths are set up urging passersby to "vote against the war" by casting mock ballots with three questions: Is the war in Iraq justified? Should a country seek the people's support before engaging in war? And should Spanish president Jose Maria Aznar and his government be thrown out of power for not seeking that support before joining the U.S.-led coalition?

Like much of Europe, Barcelona is filled with people protesting the war. What sets the city apart from other European countries – and certainly most of the U.S. – is that alongside anger and frustration is an almost jubilant sense of freedom in personal expression that fuses the political with the personal and the artistic. These are people who know they have the right to take to the streets every weekend, camp out in the squares and loudly declaim the war without fear of government reprisals or lines of riot cops.

As we immersed ourselves in the exuberant spirit of Barcelona, we slowly began to let go of the baggage of fear that we had brought with us from the United States. The feeling was one of overwhelming relief. We felt released not only from the fear of speaking out, but also from the more overarching fear that fuels it: the fear of terrorism. That fear of loss – reaffirmed repeatedly by our government and our media since 9/11 – has seeped into our consciousness as Americans, filling us with a constant sense of foreboding. But in Spain, people sing, dance, and bang their pans. They smile.

Our bubble of exuberance is punctured almost immediately after we get off our plane back to Boston. As we file through the second set of in-depth security checks, an American employee of the airline points at our red, white, and black anti-war pins and asks us sternly what it means. We answer and sense his disapproval, delivered in a long look and renewed questions about our business abroad. Within minutes, the pins we couldn't put on fast enough in Barcelona had become statements that made us feel uneasy and out-of-place. We now live at a time in this country when we are made to feel ashamed and not empowered when we defy authority.

Michael Blanding and Alexandra Hall are senior writer and features editor, respectively, at Boston Magazine.