There are career detours, and then there are career detours. As such things go, the path chosen by Tom Morello in recent years has been a doozie. Best-known for his dazzling six-string work in Rage Against the Machine and Audioslave, the 47-year-old guitarist was inspired, in 2003, to don the guise of acoustic-guitar-and-harmonica-wielding protest singer. Dubbing his alter-ego The Nightwatchman, he’s since released two full albums and one EP that owe more to Phil Ochs and Woody Guthrie than to any of his electric-guitar-playing forbears.

Morello’s latest Nightwatchman album, World Wide Rebel Songs, finds him mixing full-on arrangements into the quieter fare. Morello’s songwriting skills continue their upward trajectory, as he unfurls styles that range from sailor songs (“Stray Bullets”) to black-sky ballads (“Branding Iron”) to folk-punk anthems (“Black Spartacus Heart Attack Machine”). In the following interview, he talks about the genesis of The Nightwatchman, the project’s evolution thus far, and the rise and fall of the alternative rock explosion of which Rage Against the Machine was a part. He also cites the five albums that influenced him most, offering details about the impact each of those discs had on him.

Is it true that a talent show at a homeless shelter helped inspire The Nightwatchman project?

Yes. That was very impactful in the sense of pushing me out of the nest, and making me want to do more than just strum around the fireplace at home. It was a Thanksgiving event at a teen homeless shelter called Covenant House, in Hollywood. Each year they have a talent show and a dinner, and I would go there and emcee. There was a 19-year-old kid there who was really down and out, with a troubled past and a potentially troubled future. He didn’t have a great voice, but he stepped up to the mic and sang as if the soul of everyone in the room was at stake. He obviously just thought, “I’ve got some ideas in my head, and I can put three or four chords together.” What he was doing felt important in a way that a lot of music on the radio doesn’t. I thought, “Man, I really want to get involved in something like that.” It made me want to go out and do this in front of people.

Each Nightwatchman album has featured more full-band arrangements than the previous album. How did that play out?

That’s true. The first album, One Man Revolution, is very stark, and very much a “three chords and truth” sort of thing. With The Fabled City, we moved toward more fleshed out instrumentation. Both those albums were produced by Brendan O’Brien, and he was the principal backup musician on most of The Fabled City. The short answer is, for the tour for The Fabled City I brought a full band with me – the Freedom Fighter Orchestra. It’s a great band – a group of talented friends who all share a great chemistry. So, for the Union Town EP and for World Wide Rebel Songs, I wanted to bring that band into the studio. I was really happy with the results. There’s a lot of electric guitar playing on World Wide Rebel Songs, and some electric guitar solos, but it keeps intact the Americana vibe of the first two albums. There’s just a lot more “Tom Morello” there, to go with The Nightwatchman.

How did it feel, at first, to perform solo in coffeehouses and at open-mic nights?

I felt I was connecting with audiences in much the same way that that homeless kid at the shelter was. I found myself taking more chances, not so much as a guitar player but as an artist. That’s certainly filtered through all of my work since then, especially The Nightwatchman stuff.

You’ve always used a very simple gear set-up. Is that a matter of pride, or is it because you feel that using lots of effects might de-personalize your style?

I would say it’s more the former than the latter. A lot of players, when they get a record deal, run to Guitar Center and buy a bunch of new gear and try and figure out how to work it. I decided early on not to do that. That freed me, in a way. I managed to find a wide variety of sounds within that very limited set-up.

When Rage Against the Machine rose to prominence in the early ’90s, music was becoming a galvanizing social force, much like it had been in the ’60s.  You once pointed out that the bands who made that happen – Rage, Nirvana, Pearl Jam and others – didn’t have commercial ambitions that were commensurate with their talents. And that screwed them up. How so?

Well, in some ways it screwed them up. Those bands – and you can list them, from Nine Inch Nails, Tool, Rage, Smashing Pumpkins, Jane’s Addiction, to the Seattle bands – shared one thing: they all had a love of underground music and punk rock. They all loved “no sell out” music. But then, suddenly, they found themselves able to play the same venues that bands like Poison were playing, and to be on MTV between videos of Backstreet Boys and those type [of] artists. It created a sort of “arena rock” personal crisis. It clearly affected them.

In what way?

It’s no accident that Nine Inch Nails albums and Tool albums and Rage Against the Machine albums came out only once every four or five years. There was none of that thing of putting out an album every six months to try to capitalize on momentum, and try and become the biggest band in the world. These bands were all vexed, and afraid of being seen in the same light as the bands they disparaged, or the bands their heroes had disparaged.

And then, of course, other bands came in to fill that gap.

That’s right. Those bands from the first few years of Lollapaloozacreated an audience, and then they didn’t serve it. Inside every cigar-smoke-filled record-label board room in the country, executives were saying, “If only we had a Rage Against the Machine that sang about girls, and would show up for a video shoots.” And those types of bands did show up. And then of course everything got diluted. They had the form but not the content. There were the nu-metal bands, the Pearl Jam wannabe bands – bands that sold millions of records, but who had nothing like the talent of the groups they were trying to emulate.

Both Rage and The Nightwatchman are fierce advocates for social and political change. Rage does that loudly, and The Nightwatchman does it quietly, for the most part. Which inspires more action among listeners?

The message of Rage Against the Machine – Zack’s lyrics – is delivered in a powerful and impactful way. The spoonful of sugar that makes that medicine go down is the thundering, undeniable rock music and funk music that Rage delivers. That’s created rebels around the globe, over the course of the last 20 years. With The Nightwatchman stuff, it’s very different. I’ve discovered that sometimes a whisper can be just as effective as a scream. Certainly the commercial impact of Rage Against the Machine far outstrips the solo stuff, but to me the latter is no less important.

Tom Morello on the five albums that influenced him most:

The Clash – London Calling

“This album showed me that music and activism could be one. They were the band who played my favorite music, plus I shared ideas with them. Prior to hearing The Clash, I liked the music of bands like KISS and Black Sabbath, and I liked the ideas of people like Martin Luther King and Malcolm X and Che Guevara. The Clash brought all of that together for me.”

Bruce Springsteen – Nebraska

“This album cracked a window into the dark heart of America that I felt growing up in suburbia, but had never heard on a record before.”

Led Zeppelin – II

“There’s nothing that rocks me like a great riff played the right way, and this album is the mother lode of great rock riffs.”

Public Enemy – It Takes a Nation of Millions to Hold Us Back

“Chuck D is one of the most important lyricists of all time. The revolutionary lyrics that he spits out on this album are matched by the revolutionary musical content. Nothing had sounded like this before, and no one had said what he was saying, on an album.”

Bob Dylan – The Times They are A-Changin’

“This album influenced my Nightwatchman solo career more than any other album – not for songs like ‘The Times They are A-Changin’,’ but for the piercing dark songs, the songs that really capture the fear and poverty and hopelessness that’s woven into parts of our nation’s DNA. Dylan saw it with a clear eye, and he sang it with three chords and the truth.”