A week ago, a friend sent me a YouTube video that I've felt compelled to share with anyone and everyone who's come into my presence. In the corner of someone's living room, four American bluegrass musicians in black suits bang out a cover of “Chop My Money”, a huge hit for Nigerian R&B duo P-Square, on banjo, fiddle, guitar and upright bass.

As the members of the band, the Henhouse Prowlers, wend their way through verses in Nigerian pidgin and Yoruba, the Nigerian guests, sitting on sofas for the house concert, pull out their phones to record the sight.

When the band finishes by chanting “Plenty dollars in my name, plenty naira in my name”, one of the audience members presses a 500-naira note to the chest of the banjo player, a gesture common throughout West Africa to congratulate musicians for a superlative performance.

It's hard to appreciate the audience's reaction without knowing a bit more about P-Square. Twin brothers Paul and Peter Okoye founded the group in 2000 and have been a dominant presence on the west African music charts ever since. Their lavishly produced music videos garner millions of views and top YouTube's charts across the African continent and, frequently, in the UK and the US. “Chop My Money” may be the catchiest of their hits, and it features Senegalese-American rap star, Akon, whose Konvict record label now distributes P-Square's music. If you wanted to pick a song that would bring Nigerian audiences to their feet, “Chop My Money” is an awfully good choice.

I had to know how this video came about, so I called Ben Wright, the banjo player and co-founder of the Henhouse Prowlers to learn how a Chicago bluegrass band that plays bars and festivals in the U.S. 220 days a year found itself performing in the living room of the US deputy consul in Abuja, Nigeria. The answer is both simple and remarkable: the US State Department's American Music Abroad program.

Sixty years ago, Adam Clayton Powell, Jr., proposed that the US could one-up the Soviet Union in a cold war contest of culture by matching the Bolshoi Ballet with America's most powerful cultural export: jazz. Under the auspices of the “Jazz Ambassador” program, the US State Department sent Dizzy Gillespie to Iran and Louis Armstrong to the Congo, giving international audiences music that was livelier than Soviet symphony orchestras, and conveying a complex political message. The touring bands were racially integrated – a potent counterweight to international news stories about segregation in the US south – and the very structure of jazz, with the soloist's freedom within the structure of the chord changes, contrasted with the rigid classical music brought abroad by the Soviets.

The State Department no longer sends artists with the visibility of an Armstrong or a Gillespie abroad. Instead, they offer ten “American roots music groups” multi-nation tours to perform and conduct workshops with local musicians. The definition of “roots music” is admirably wide: “The diversity of traditional American genres we are seeking, includes, but is not limited to Contemporary Urban , Hip Hop, Rock & Roll, Punk, Heavy Metal, Indie Rock, R&B, Jazz, Blues, Country, Broadway Musical Theater and American roots music genres like Country, Gospel, Soul, Bluegrass, Zydeco, Cajun, Afro-Caribbean, Tejano, Southwestern American Conjunto, Native-American and Folk.” (I have high hopes that Indonesia's election of metalhead Joko Widodo to the presidency means that a diplomatic tour featuring Megadeth is in the cards.)

Ben explains, “The Prowlers have been doing educational outreach, performing and teaching in US schools for years. We figured that might give us an edge.” The Prowlers were one of forty bands selected to audition and won one of the ten slots for 2013, leading to a tour of Congo Brazzaville, Liberia, Mauritania and Niger. Bands have no say over where the State Department will send them, but Ben could not have been more thrilled to travel to West Africa. His father is African historian Donald Wright, who specializes in The Gambia, and he'd traveled with his father almost two decades earlier. “When I heard about the trip, I called my father, who basically lost his mind. I was getting the chance to travel to places he'd dreamed of going, Mauritania and Niger especially.”

Ben and the band discovered that touring West Africa had unexpected joys and challenges. “You spend six hours cramped in a car, traveling through the Liberian jungle over terrible roads. But when you get there and put on a show, collaborating with local musicians, it's always worth it.” His instrument of choice helped build connections as well. In Niamey, Ben found the Henhouse Prowlers paired with a Nigerien band fronted by a man playing the Akonting, the “great-great grandfather of the banjo.” While traveling bands don't have much time to bond with the local players – only two hours to meet, set up and soundcheck – he and the Akonting player bonded immediately. “I tuned my banjo down two steps and suddenly we were in key trading licks back and forth. It's hard to know how well you're connecting, given the language and cultural barriers, but he was smiling and I was too.”

The chief lesson Ben took from the Prowler's first African tour – play recognizable music. So when they got a request from the US embassy in Nigeria to play an Independence Day concert in Abuja, Ben asked what songs were popular in Nigeria. His embassy contact sent him a list of YouTube links, including a number of P-Square songs.

“We picked ‘Chop Your Money’ almost at random, not realizing how popular it was,” Ben told me. “It was no small undertaking to learn it.” The song has four verses and each member took responsibility for memorizing one, an especially tricky task with the verses in pidgin English and Yoruba. The band's relentless touring means there's little time to rehearse, so the song came together, in part, on stage as the Prowlers tried it out in front of polite, but confused, US crowds.

The reaction in Nigeria was significantly warmer. “When Jon (Goldfine) started singing in Yoruba, people lost their shit.” In the audience in the deputy consul's living room was a Nigerian parliamentarian, who called Peter Okoye of P-Square to tell him about the bluegrass cover of his song. A few days later, Okoye met the Prowlers backstage before their Independence Day show in Abuja and told them, “I'm here, and you know what I'm here for.” They didn't realize Okoye's plan was to join them onstage, and you can see the shock on their faces as the singer sidled to the stage and took the mic from fiddle player Dan Andree.

After receiving P-Square's blessing, the Prowlers set out on a tour of radio stations and live performances in Lagos. “We'd walk into these radio stations and the host would be deeply skeptical, not knowing what these white boys in suits were doing here,” Ben recalled. “We'd play ‘Chop My Money’, the phones and Twitter would light up, and by the time we left, they'd be asking for autographs and putting photos of us on the wall. Then we'd leave the station and cars would honk at us because they'd heard the song on the radio.”

A little pidgin goes a long way. The US ambassador to Nigeria – who has a front-row couch seat in the video I was sent – James Entwistle got a warm response when he answered a question on Wazobia FM Lagos about the US's position on Nigerian's approach to gay rights in pidgin, telling the audience “The U.S. government no say sanction go dey for Nigeria, because of same-sex palava-o.” The ambassador won kudos in Nigeria and abroad for making the effort to learn Nigerian culture and connect directly with ordinary Nigerians outside of diplomatic circles, much as the Prowlers did by incorporating P-Square into their repertoire.

If the Jazz Ambassadors of the 1950s and 60s used soft power to export American culture and values to the wider world, the message from American Music Abroad is more subtle and humble: we're listening. Many of the performances the State Department has made possible feature American performers learning from local masters, and showing how the musical encounter is changing both participants.

The Nigerian experience has certainly changed the Henhouse Prowlers. “Chop My Money” is now part of the band's regular set. “We like to tell stories as well as play songs, and the stories associated with this song are some of the best I've got,” says Ben. Soon, it may not be their only Nigerian tune. “We're talking about going into a studio and recording an EP of Nigerian music which we can send to the radio stations that played us in Lagos. I'd like to see us take on some Fela, to look into the past as well as the future of Nigerian music.” As video of their Nigerian performance has spread online, the band has received some unexpected invitations. “We got invited to Calgary, Alberta to play a Nigerian cultural festival. A Nigerian couple in Atlanta asked if we'd play their wedding.”

Whether or not the State Department is covering the bill, Ben is determined to bring bluegrass back to West Africa. “I know why my father kept coming back to West Africa. I've caught the bug.”