If you’re anything like me, you know of Iron Man from the Black Sabbath song, not the Vietnam-era comic book that inspired it. But out in the hinterlands of fandom, Iron Man remained a popular Marvel superhero, even if Hollywood never lifted him from pulp pages to the big screen. It wasn’t for lack of interest. The one-man panzer division moved from studio to studio, attracting and repelling actors and directors. After more than 10 years in development, Iron Man has finally arrived, with Robert Downey Jr. in the title role and director Jon Favreau (Elf) behind the viewfinder.

Downey looks comfortable as Tony Stark, smart-alecky heir to Stark Industries, America’s leading weapons-maker. We meet him in a Humvee racing down a dusty Afghan road, the ice in his glass of Scotch rattling with every bump along the way. He’s just demonstrated a new secret missile for U.S. commanders (why would they do this in a war zone?) and is yukking it up with the troops when bombs detonate all around. He has his first shock of recognition: His own company manufactured the shell that lands nearby, shredding his GQ suit and blowing him into the dust. Maybe Downey relates to Stark personally. Like him, he’s a 40-something high-flyer undergoing a sea change. Downey seems to have beaten his drug addiction. Stark learns there is more to life than destroying it.

A sneaky streak of subversion runs through parts of Iron Man, which validates America’s mission in Afghanistan and supports the troops while taking the air out of the tires of the military-industrial complex that profits from the enterprise. Before his change of heart, Stark was a blowhard super-patriot, “ensuring freedom” by devising and selling smarter bombs. An irresponsible wastrel, he had the redeeming feature of being a hands-on inventor of the tools of his trade. His skills helped him build the original bulletproof Iron Man suit while captive in an Afghan cave. The clanking contraption allows him to mow down the Al Qaeda stand-ins and escape.

On returning home he announces at a press conference that he “has more to offer the world than making the weapons that will blow it up,” but is quickly undermined by rapacious industrialists. His corporate board not only wants to continue Stark Industries’ profitable relationship with the U.S. military, but has found new customers in the terrorists America is fighting. This makes Tony Stark mad. Very mad.

Favreau keeps the tone light; there are many funny moments, but also long stretches of glibness. Written by a half-dozen authors working at different times with different agendas, the screenplay is a mess held together on the thread of indifferently filmed action scenes. Iron Man is as aware as any astute cable news viewer that everything reported has been given a certain spin. At the same time, the plot is littered with irritating clichs, including the familiar, jovial African-American sidekick and even the “good native” in Afghanistan who for no good reason gives up his life to save the white man.

Special effects? The computer icons that come alive as three-dimensional holograms in Stark’s basement workshop are cool, but the sleeker Iron Man costume he devises down there to battle the evildoers isn’t especially impressive in flight. The aerial antics are reminiscent of an amusing Disney movie from the early-’90s, The Rocketeer, except not nearly as well executed. The technology of computer imaging is no substitute for cinematic imagination. Just because you can do it doesn’t mean it looks good!