Platinum-selling rock ’n roll guitar players aren’t often on the front lines of political activism one night, then shouting encouragement to kindergarten-aged ballplayers the next morning. But Tom Morello is no garden-variety guitar hero.

The 51-year-old Los Angeles-based musician, songwriter, activist, record label head, husband and father— who will appear Sunday at the Claremont Folk Festival —is nothing if not tireless.

The 1986 Harvard grad has in recent years recorded with and toured as a member of Bruce Springsteen’s E Street Band; co-founded a record label and signed acts from around the globe; released four records from his folk-minded project, the Nightwatchman, and two others from another side-project, the Street Sweeper Social Club; has continued his political activism and community outreach projects and has somehow managed to maintain a relatively normal life as a husband and father to two young boys, ages five and six.

“The full immersion in parenthood is the most gratifying thing I’ve done,” he said. “It sharpens my commitment to pushing forward the struggle for a more just and humane planet, because my kids are going to have to grow up in it.”

The struggle Mr. Morello has been fighting for nearly 30 years is one of leftist political engagement in this country and abroad. He curates “Firebrand Fridays” at venues around Los Angeles, with proceeds benefitting local homeless charities. He co-hosts a radio show on XM and KPFK through his nonprofit Axis of Justice, which he co-founded with System of a Down’s Serj Tankian. And Mr. Morello has taken his activism abroad, participating in occupy protests in several UK cities.

His musical career includes founding hard rock/hip hop pioneers Rage Against the Machine in 1991—who went on to sell more than 10 million records before the band’s first breakup, in 2000—and Audioslave, another multi-platinum group that featured the core Rage band with vocalist Chris Cornell of Soundgarden. Rage disbanded in 2007 but reunited shortly after, touring the world and headlining huge festivals. Rage’s most recent appearance was in Los Angeles in 2011.

At press time, however, the Internet was abuzz with speculation regarding a Tweet from Rage’s official Twitter account that referenced a new website named for a vintage tune (“Prophets of Rage”) from hip-hop giants Public Enemy. It included the hashtag “#TakeThePowerBack,” the title of a track off Rage’s debut record. The cryptic post was tied to a time clock counting down to June 1. It would seem Rage Against the Machine is about to be re-booted in some manner, with Public Enemy involved in some capacity as well.

In the meantime, Mr. Morello finds himself re-jiggering his modus operandi, as the lovely demands of fatherhood have changed the way he does business.

“It’s certainly re-oriented my priorities,” said Mr. Morello of his role of father and little league coach. “My 10,000 hours were once dedicated to shredding on the guitar; now, my 10,000 hours are spent at little league practice.”

At Sunday’s Claremont Folk Festival, Mr. Morello will perform with his Nightwatchman configuration, a duo act with longtime collaborator, guitarist and vocalist Carl Restivo.

“He’s the Garfunkel to my Simon,” Mr. Morello joked. “He is the consigliere of the Freedom Fighter Orchestra,” the guitarist’s touring band. “He frees me up to play a little electric guitar as well. There will be a healthy dose of shredding to go along with the folk balladry. But the Claremont Folk Festival is steeped in the history of folk music, and that is the torch that will be burning.”

Shifting from the heartland rock and workingman’s blues of the E Street Band to the fiery activist folk of the Nightwatchman entails more than a little versatility. It’s a task Mr. Morello takes on willingly.

“I’ve never been afraid to follow an artistic muse, whatever direction it led me,” he explained. “I really love the folk music genre best of all. I came to it later. I grew up on metal, punk and then hip hop. It wasn’t until the early days when I was touring with Rage Against the Machine when I really got into the early Dylan records and Woody Guthrie and Bruce Springsteen’s “Nebraska” record. I’d always been drawn to heavy music, but I realized those three haunting chords and right lyrical couplet could be as heavy as anything in the Metallica catalog.

It seems that Mr. Morello’s music side is about to ramp up significantly, what with the mysterious Rage Against the Machine Internet rumblings and that time clock ticking down to June 1. But still, he seems to have a clear grasp on the all-important balancing of family and career.

“My first priority is to never shirk my duties and responsibilities to them [his sons],” he said. “I’m doubly committed through my vocation as a guitar player, as a songwriter, as a singer, as a record maker and as a performer to continue to fly the banner of fighting for social justice while at the same time raising two little revolutionaries who are excellent clean-up hitters.”

The Nightwatchman appears at 6:30 p.m. on Sunday, May 22 at the 33rd annual Claremont Folk Festival at Pomona College’s Sontag Greek Theater, 300 E. Bonita Ave. Doors open at 3 p.m. Also on the bill are Quetzal, Yuval Ron and David Lindley. Festival tickets are available at the Folk Music Center (220 Yale Ave.) or at brownpapertickets.com/event/2527695.

More information on Tom Morello is available at nightwatchmanmusic.com.

—Mick Rhodes

mickrhodes@claremont-courier.com