Fifteen years ago, James Cameron turned a tragic maritime disaster into a romantic disaster epic cum box-office-shattering pop-culture phenomenon. “Titanic” was the first film ever to gross over a billion dollars worldwide and scooped up 11 Oscars. It confirmed Leonardo DiCaprio and Kate Winslet as rising A-list stars and even made Billy Zane briefly relevant, a feat that I think might be even more impressive than the film’s revolutionary special effects.

With the centennial of the actual sinking of the RMS Titanic fast approaching, Cameron has decided to try catching lightning in a bottle for a second time (or third time, if you want to count “Dances with Blue Cat People”), post-converting his blockbuster film to 3-D and rereleasing it into theaters. Why, you may well ask. I can give you five reasons off the top of my head, the first four of which are “because MONEY.”

The fifth reason is that, say what you will about James Cameron, the man is fiercely dedicated to advancing cinematic technology, and if anyone is going to make 3-D work it will probably be him. I normally avoid 3-D whenever possible, but I made an exception for the “Titanic” rerelease so that I could a) see if Cameron could make anything out of the post-conversion process that has plagued so many other films, and b) revisit the film, which I concede I have mercilessly mocked and derided for over a decade now (a tendency that sort of goes against the “objective critic” persona).

Much of my antipathy toward “Titanic,” I now realize, came from never having seen the film in the theater. The Titanic itself was all about spectacle, a marvel of both engineering and luxury, and Cameron shot his film with the same “bigger is better” principles in mind. And, in this case at least, he was right: it’s impossible to grasp the sheer enormity of this film on your home TV or laptop. The sinking sequence, which occupies the entire second half of the film’s unwieldy 194-minute running time, is absolutely breathtaking. The audience knows full well what will happen, and Cameron plays with that knowledge, slowly building a sense of dread beat by beat, moment by moment, until the astonishing chaos and pandemonium of the ship’s final moments.

Part of what makes this part of the film so effective is, of course, the special effects, which have aged extremely well. That’s probably thanks to Cameron’s insistence on using enormous scale models and stunt performers rather than CGI as much as possible; there’s a tangibility to the ship and the people onboard that is lacking from many similar disaster films (see “2012,” “The Day After Tomorrow”) and exponentially increases the terror and disarray of the images.

Ideally, the 3-D would add to that fear by putting the viewer right in the middle of the mayhem. Alas, other than a few shots of rushing water that benefit from the increased depth of image, all the 3-D adds here is a litany of complaints that Hollywood should be familiar with by now: the picture is noticeably darker, backgrounds are blurry and the shots are divided into distinct, flat planes, resulting in some unsettling, actively distracting compositions. Yet perhaps most damning (and simultaneously reassuring, if you’re planning on buying a ticket) is the fact that most of the time, the 3-D isn’t even noticeable. I love the idea of putting large-scale movies like “Titanic” and “The Lion King” back into theaters for limited runs, but Hollywood shouldn’t tack on useless, price-inflating gimmicks to do so.

Is the spectacle and visual effects all there is to “Titanic,” though? The film mainly gets criticized for its drippy dialogue and hackneyed performances, but is there really nothing salvageable in the romantic subplot? This is not just a conjectural exercise; it’s critical to whether the film works at all. The entire first half of “Titanic” relies on the love story between the adventurous, lower-class rascal Jack and the repressed, prim rich girl Rose — there must be something that makes it tolerable for viewers, male and female alike, to make it through to the thrilling, drawn-out climax.

Upon revisit and reflection, Cameron’s screenplay is still as atrocious as ever. Far too much time is spent setting up the story’s modern-day frame, as Bill Paxton (Treasure Hunter!) and his crew search for a lost diamond necklace amid the wreckage of the Titanic. I know Cameron is really into oceanography and boat science and everything (he recently dove into the Marianas Trench in a submarine of his own design – seriously) but it’s incredibly irrelevant to the romantic epic he’s supposedly telling. And yes, much of the dialogue is clunky and schmaltzy. But I see all that now in a world where Nicholas Sparks’ adaptations and facsimiles completely dominate the romance genre (there was a preview for “The Lucky One,” the latest maudlin Sparks film starring Zac Efron, before “Titanic”). If I have to pick, I’ll admit I would much rather watch Cameron’s broad style – he uses archetypes in service to the story, rather than as the story and fills out the basic romance template with a unique setting and an array of vivid supporting characters. Even if Jack and Rose are a bit drippy, there are still poignant moments to be had in tracing the tragic arc of some of the minor roles (I was particularly fond of the ship’s designer, Mr. Andrews, and the string quartet that plays on as the boat sinks, meeting their deaths with dignity and gravitas).

And while Kate Winslet doesn’t do much to invigorate Rose’s paint-by-numbers half of the narrative, I was surprised to find myself drawn to DiCaprio’s charming performance. Early in his career, Leo seemed to be cast in roles mostly for his pretty boy looks, but you can really see his talent as an actor starting to emerge here, particularly in the subtle skepticism he exudes during his interactions with Rose’s snooty family.

Serious-minded critics hem and haw about calling Cameron a great director (partly because the man seems to be an obnoxious boor), but the fact is that he is very good at telling engaging, simple, epic stories. “Titanic” may have the psychological complexity of a soft-core porno and undoubtedly drags on for too long, but it’s all in good fun.