Define hoedown.

Last year, an exhibit on marine life at a local museum featured placards informing kids that many of the featured species are nearly extinct; a co-worker's nine-year-old daughter has panic attacks over global warming. It's growing difficult to educate our children about the importance of caring for our enviroment without terrifying them into apathy; one of the many triumphs of WALL-E is how it speaks directly to a child's anxieties about the future, neither patronizing nor indoctrinating its young viewers. A cartoon of surprising sadness and thematic heft, WALL-E is remarkable in the way it gently suggests that the solution to our problems lies in our capacity to love one another. Effortlessly connecting its sweet love story with universal human concerns, WALL-E is, along with movies like AI, Solaris and Eternal Sunshine of the Spotless Mind, another of this decade's sci-fi masterpieces concerned with finding love in a world transforming before our eyes.

Another of WALL-E's astonishments is the way that it makes Hello Dolly! not only palatable but moving; a jolly number from the musical introduces us to an Earth 700 years in the future that has become an abandoned, trash-strewn wasteland. As humans have abandoned the planet to reside, fat and compacent, in an enormous shopping center, a small robot named WALL-E remains alone, his days spent compacting trash while his nights are devoted to showtunes, bubble wrap and other prized artifacts. It's impossible not to be moved as the little guy makes his way across vast expanses of scorched earth littered with towering trash heaps and plagued by dust storms, all the while whistling a tune. The animators have created a frighteningly believable future that would be the stuff of horror movies were it not for the geniuine, guileless optimism that seems to be an intrinsic part of Pixar's philosophy. When WALL-E's centuries-long isolation is broken by the sudden arrival of search robot EVE - her egg-shape signaling the return of femininity and, more specifically, fertility - his attempts at romance, which remind of Chaplin's Little Tramp in both their hilarity and poignant persistance, suggest that the key to our future lies in holding hands. It's a cute idea, but as WALL-E's thematic implications sink in, it's also surprisingly powerful.

Structured like the Kubrick movies it pays homage to, WALL-E also expands to include sly satire as the robots travel to the spaceship. Writer/director Andrew Staunton gets a lot of laughs in at our complacency and rabid consumerism, as humanity has become a flock of portly, immobile proles. It's unsparing stuff for a kid's movie, stopping short of misanthropy by arguing that most people simply need a little wake-up call. And WALL-E is just that - as Pauline Kael once said about Nashville, it loves us too much to patronize us. In the moral awakening of the ship's captain (Jeff Garlin) lies a powerful reminder of the obvious - Earth is awesome, and worth taking care of. And while I shudder to think of all the Humvee-driving parents who dismissed any questions their kids might have had after the movie, I still love the idea that the seeds of change have been planted in their heads.

But even if you're not a tree-hugging hippy, WALL-E is still worth your time. Staunton and his team of animators balance near-wordless physical comedy worthy of Keaton with a breathtaking vision of the future worthy of Kubrick or early Ridley Scott. WALL-E astounds in moments both grand (WALL-E reaching out to touch phosphorescent blue space debris) and mundane (the robots' shared fascination with the flame from a cigarette lighter). And at the film's heart is a man-made protagonist that, through his selflessness, compassion and bravery, personifies all that is great in us. Sound designer Ben Burtt, who gives WALL-E his voice, did the same for E.T. - like Spielberg's masterpiece, WALL-E finds just the right note of hope at a time when it is most needed. Were it simply funny and brilliantly animated, WALL-E would be another in a string of great Pixar movies; add in its rich ideas and its giant heart, and you have a movie that deserves to be a perennial classic.