NASHVILLE -- America loves its outlaws, and few are as admired and lionized as Willie Nelson.As the enduring Texas icon's 80th birthday has approached, he has been honored with lifetime achievement awards, serenaded at special performances and saluted by musicians from every genre of music. And Nelson has taken it all in with a bemused smile."It's a nice thing to do for someone on their birthday, and I appreciate it," Nelson said in a recent interview aboard his bus. "Usually I like to forget my birthdays as much as possible."The hubbub is as much about celebrating Nelson as it has been celebrating with Nelson.The singer whose birthday is today or Tuesday -- Nelson says April 29, the state of Texas claims April 30 -- occupies a unique space in America's cultural memory. A walking bag of contradictions, he wears his hair long in braids and has a penchant for pot smoking, yet remains arguably conservative country music's greatest songwriter. He's accepted by left and right, black and white, and is instantly recognizable to a majority of Americans.Outlaw and maverickHe is also a Texan first, born in Abbott and the centerpiece of his own Fourth of July concert bash, a legendary concert party staged at Billy Bob's Texas in Fort Worth.On Sunday night, he gave a sold-out show outside Austin to help raise money for the West volunteer fire department, decimated by the April 17 fertilizer plant explosion that killed a dozen emergency responders.Like few other music stars, his image has grown to represent more than the notes he has played or the lyrics he has written. Like Elvis Presley, Johnny Cash or Frank Sinatra, he's become a figurehead for a uniquely American way of thinking. He represents the outlaw and the maverick."America is a bizarre place, and Willie is our captain," said Jamey Johnson, Nelson's good friend and sometimes opener.Road warriorNelson didn't set out to be a folk hero, as Charles Kelley of Lady Antebellum calls him. He spends something like 200 days on the road still, a pace that challenges men a quarter his age.In a series of interviews over the last year, Nelson explained he just came to Nashville wanting someone to buy his songs. That young man never imagined he would be on the road for more than 50 years. His first real songwriting job paid $50 a week. He played -- and sometimes slept -- at Tootsie's on Lower Broadway in Nashville, just a few miles -- but really a million miles -- away from Music Row.Nelson thinks that young man wouldn't know what to make of the spectacle he has become."He'd probably wonder what's that old man doing out there," Nelson said with a chuckle. "He's got a house. He's not homeless. Why don't he go home?"The truth is Nelson is home as he sits at the pleasantly cluttered kitchen table of his bus. With its portrait of an American Indian on the side, the bus is as much a part of Nelson's mythos as his braids and battered old guitar.An invitation to join Nelson on the bus is coveted."I've never smoked weed ever in my entire life," Lady Antebellum's Hillary Scott joked. "But if I got invited on the bus I might have to make a concession just because of purely what it is, what it represents."For Nelson, it's a refuge, office, songwriting room and parlor where he hosts friends and band members for morning coffee."I've lived in this house longer than I've lived in any of the others, all combined," Nelson said glancing around. "I feel at home here. It moves around. I have a mobile home. That's about the size of it, and I enjoy it."Nelson has pursued this nomadic lifestyle for more than four decades, almost unchanged. The band has remained the same. Until recently, harmonica player Mickey Raphael was pretty much the new guy. He recently celebrated his 40th anniversary with Nelson.Nelson hangs onto his buses till they're over a million miles, still wears a black T-shirt and that red, white and blue guitar strap. His children grew up on the bus, and now they play in his band from time to time.So, to paraphrase Waylon Jennings, the outlaw thing's been overdone. All he wanted to do was play his own music the way he chose. In Nashville, that idea was considered sacrilegious at the time."You ever heard the song me and Waylon did back in the old days called Write Your Own Songs?" Nelson says with a laugh. "I still do that one occasionally. I get a kick out of doing it because it takes you back to the days when me and Waylon were fighting the outlaw wars here in Nashville and losing. I enjoyed those times. I even enjoyed being the outlaw and the outcast. I thought, 'All right, that's great. I must be doing something right.'""You remember the old saying, 'You keep on doing it wrong till you like it that way?'"