Terrified of serpents, I knew to avoid the snake charmers of the Jemaa el Fnaa market in Marrakesh. But my son Alexander also warned against having my picture taken with any of the performers in the square.

We had just arrived from Fez, where I had given a presentation, and were making our way through the chaos of the market. This was like no other place. All around us we heard music representing the traditions of the Amazigh, the indigenous people of Morocco, commonly known as Berbers. Storytellers entranced huge circles of listeners with their narratives. Men holding monkeys were pursuing visitors, Moroccan and tourists, for photographs. And with the corner of my eye, I could make out the cobras swaying to the reedy vibration of the oboe-like ghaitas.

Overwhelmed, we headed for one of the terrace cafes surrounding the square. As we sat down with a glass of mint tea, we couldn’t really focus on any of the sights, so many were the riches before us. It was like trying to detect individual drops in a rain shower. But nearer to us we picked up loud, syncopating drums from a group of Gnawa musicians. Dressed in saffron robes with yellow sashes and wearing the tarboush, hats with long tassels, they beat their drums and struck their cymbals as they shook their heads in circles.

In a strange way the music seemed familiar to me. The night before in Fez Alexander had taken me to a café for a Gnawa performance by Rayan, his music teacher. Rayan had lived in Paris as a rap artist and break-dancer before returning to Morocco a few years later to study Gnawa music. Dressed in the fashion of the performers before me, he played his ginbri, a plucked string instrument similar to a banjo, accompanied by a singer who played large castanets called the grageb. Rayan was my introduction to the numinous, hypnotic rhythms of Gnawa.

From the corner of the room, I could see the other patrons clapping their hands and swaying to the trance melodies and sometimes joining in the song. They rolled tobacco into their cigarettes. And I, a foreigner, allowed myself to feel the waves. The room was a warm glow against the cool November night of the desert. I leaned against the wall and welcomed the heavenly calm. It did help, as Alexander later told me, that the patrons fortified their tobacco with hashish. Smoke was everywhere.

And then suddenly someone rushed into the room, waved his hands and stopped the music. What happened, I asked Alexander? Nothing, he said. It was just the call to prayer from the mosque nearby. No music can play at this time.

Alexander was taking weekly lessons from Rayan and often came to the café to hear him. Once he attended an all-night ceremony during which Rayan played for seven hours with only a few breaks. He explained that the Gnawa music originated in sub-Saharan Africa and mingled with the Sufi traditions of the Maghreb.

From my perch in the café in Marrakesh, I thought of Rayan’s presentation and tried to connect it to what I was hearing below. "What was more authentic?" I wondered: Rayan, who had, like many contemporary Gnawa artists, refigured religious ritual into an aesthetic performance or the performers before me who made their money in the square, often having their pictures taken with visitors?

With the sun setting, I suggested that we go back to our riad or guesthouse. But first I thought we should make a contribution to the performers. I make a point of supporting street musicians as my older son, Adrian, has been playing his violin in the streets of New Orleans for the last two years.

So I gave Alexander some cash and instructed him to give it to one of the performers. Immediately, however, a dancer asked, “Picture?” No way, I thought. Not me. I’m not one of those people. It seemed so cheap, so touristy. “Come on,” he said. I was torn. Was it not rude to say no? But I could feel Alexander’s glare. He did not want to participate in the objectification of the other, he had told me when we entered the square. So I resisted. “Come, take picture,” the man beckoned. But in a moment of confusion, I handed Alexander my phone and then I was pulled into the dance, had a tarboush popped on my head and instructed to swirl the tassel. For a couple of seconds I had my own little orientalism.

Alexander snapped a picture and then I pulled away. “Money,” called one of the dancers. “But I gave you some,” I replied. It had been a generous contribution. “My other son is a musician,” I mumbled. “But I want my money,” he insisted. “I deserve it.” “I’m sure you do,” I thought and stepped away with lowered eyes, trying to untangle myself from the contradictions of tourism, colonialism, wealth, and poverty.

Well, I said to myself. My son is a performer in New Orleans and he gets his picture taken with patrons. But I knew this was different. Many others had come to Marrakesh before me and snapped pictures of the indigenous inhabitants, often without permission, turning them into objects of curiosity, exoticism, or sometime disdain. I did not want to be part of this, wanting to keep my conscience clean. But now the musicians were actively courting the foreign camera, frustrating my attempt to travel in peace.

This was the case a year ago in Ilorin, Nigeria, where I was invited to give presentations at Kwara State University. One night my colleagues had invited me to a performance of Yoruba poetry and dance. I was the only white face in the audience, something made apparent at the end of the show as listeners wanted to have their pictures taken with the performers.

I stood back, trying to take everything in. But all of a sudden one of the performers pointed to me. Thinking that he was mistaken, I turned to see if he meant someone else only to realize that he actually beckoned me to come up on the stage. To my bewilderment the performers had their picture taken with me. Later I asked my host, an expert in Yoruba poetry, to explain this invitation. He said the ensemble would likely use the photos in their advertising with the message that they are so good that even white people come to their performances.

In Marrakesh, as in Ilorin a year earlier, I became enmeshed in contradictions I had not expected. Although we may travel with the best intentions, we can’t help but confront tensions we find easier to avoid at home — between rich and poor, black and white, those who represent and are represented, and those passports that enable movement and those that block it.

The music I heard in Morocco expressed these inequalities. Itself a product of ethnic and racial mixing of Africa, it brought Rayan, Alexander, the Sufi performers and me together. But it also conveyed political and economic conflicts that continue to reverberate around us.