How much enjoyment you can milk out of the 155 minutes required to sit through Baz Luhrmann’s sprawling, teeming, and extremely silly epic Australia will depend on what you think about its most important character. Here I do not mean Nicole Kidman or Hugh Jackman, who technically headline the film — Kidman as the English noblewoman who inherits a cattle ranch in the late-1930s Outback, Jackman as the rugged Aussie known only as “the Drover” who becomes her business partner and then, inevitably, her lover. Nor do I mean the Land Down Under itself, whose picturesque topography is captured with swooping, soaring, God’s-eye camerawork throughout. (The Australian tourism industry has a $26 million ad campaign riding on the hope that the film becomes a hit.) No, the character I have in mind is Nullah (Brandon Walters), the half-caste part-Aborigine boy who becomes a surrogate son to Kidman’s Lady Ashley, and whose uneasy racial status provides the jumping-off point for the movie’s political ambitions.

Such ambitions are new to Luhrmann, whose past successes — his Shakespeare-as-teen-soap Romeo+Juliet and the garish pop musical Moulin Rouge — lacked any high purpose save a fierce zeal to entertain. After a seven-year hiatus, though (spent staging La Bohème and failing to stage an Alexander the Great epic when Oliver Stone’s got off the ground first), he has more serious things in mind. The result is an epic that seeks to marry Old Hollywood grandeur to New Hollywood revisionism: Imagine Gone with the Wind refashioned as anti-slavery polemic, and you have roughly the idea of what Luhrmann’s going for.

His hot-button subject is Australia’s historic treatment of its Aboriginal minority, and specifically the policy — whose actual scope is the subject of considerable debate, though you wouldn’t know it from this movie — of tearing half-caste children from their homes and raising them in orphanages, the better to turn them into proper Westerners. The quest to keep young Nullah from this fate, amid cattle drives and Japanese bombing raids alike, provides the movie with what’s meant to be its most potent through-line: The bronze-skinned, beaming boy is simultaneously a potential martyr to Australia’s racist past and a harbinger of its multiracial future.

And God, how I hated him. Not the actor, who brings a kilowatt smile and an androgynous charisma to a role he’s not responsible for crafting, but the character, who occupies the peculiar zone where political correctness shades into precisely the sort of racial stereotyping it’s supposed to counteract. Nullah grins and gambols; he chatters in a cloying patois (“we gots to drive-um them cheeky bulls, Mrs. Boss”); and he comes equipped with a mysterious medicine-man uncle (David Gulpilil) who’s a pure Noble Savage cartoon, bearded and bare-bottomed and rich with hocus-pocus. The overall effect is Little Black Sambo by way of Dances with Wolves: The condescension is intended to be favorable, but it’s condescension all the same.

But maybe you’ll feel differently — and if you do, the non-Nullah aspects of the film have enough going for them to make Australia at least an intermittently successful guilty pleasure. Luhrmann’s métier is melodrama, and at its best the movie offers the mix of sincerity, shamelessness, and spectacle that made his Moulin Rouge such a gaudy treat. The plot is a pastiche of war movies and westerns; the hero and heroine are imitations of archetypes from Hollywood’s Golden Age (Jackman is basically playing Clark Gable playing the Drover); there are not one but two hissable villains (Bryan Brown as the cruel cattle king Carney, and David Wenham as his sinister right-hand man); and whenever the narrative starts to flag, Luhrmann throws in a tavern brawl or a cattle stampede to keep things interesting. The stars are game, the scenery is stunning, and if you can suspend your critical faculties (and ignore the often dodgy special effects), there’s enough sweep here to get swept up in.

And if the hackneyed script and endless third act begin to grate — if your mind turns too often to Michael Bay’s Pearl Harbor, another big-budget love story featuring a Japanese surprise attack — it’s probably because there isn’t enough singing. The implausibility inherent in the melodramatic style is ideally suited to a musical or opera: Moulin Rouge worked so well, in part, because it demanded that the audience suspend its disbelief, by peppering the plot with realism-busting bursts of song. We know, from that film, that Kidman has pipes enough to warble through a musical, and Jackman has headlined on Broadway in the past. If they’d sung their love, instead of speaking it — if Australia had been titled Australia! — I think there would have been more in Luhrmann’s latest film to love, and less to roll one’s eyes over.

But he wanted to be serious instead. He wanted to be political, to take on racism and imperialism and the sins of Australia’s colonial fathers, and to make something more than a frothy entertainment. The result, perhaps inevitably, is a film that’s something less. Australia showcases Luhrmann’s gifts as a crowdpleaser, but not nearly often enough. You might say they’ve been Nullah-fied.