Hollywood is roundly criticised for manufacturing an endless conveyer belt of spectacle and sensationalism — an industry, so the common wisdom goes, where nothing is sacred, everything is for sale and no subject is taboo.

It’s more than a little surprising, then, that throughout the ten years since the September 11 attacks the industry has maintained great restraint in its depictions of events related to 9/11, which are few and far between. So why has Hollywood, of all places, largely kept mum about one of the biggest moments in contemporary American history?

Even firebrand filmmaker Oliver Stone, never afraid of clocking audiences on the noggin with bravado and controversy, was careful not to overdo it in World Trade Center, his 2006 action drama depicting — led by a character portrayed by Nicholas Cage — the heroic efforts of New York police and fire fighters.

Emotionally and sentimentally the film is as subtle and nuanced as an episode of Melrose Place, but Stone was careful not to make it a parochial war piece. Instead he shaped it in the mould of a Hollywood disaster pic, fashioning World Trade Center as a universal story about courage and triumph in the face of adversity. It’s not a good movie — despite tissue box sentimentality, it is oddly unaffecting — but, strictly in terms of subject matter, it is a unique one.

So too is director Paul Greengrass’s terrifying United 93, the closest to a masterpiece of any 9/11 film (which would mean more if the playing field wasn’t so small). Presented as a real time re-enactment of the highjacked plane that crashed near Shanksville, Pennsylvania, after passengers thwarted the terrorists’ plans, Greengrass maintains startling verisimilitude throughout a story in which all the principal players (sans those in the control room) are doomed.

In terms of movies that directly confront what happened on September 11, 2001, World Trade Center and United 93 are, amazingly, just about it. To find other 9/11 Hollywood ventures requires one to dig considerably deeper.

An interesting example arrived from an unexpected place: an Adam Sandler film in which Sandler plays, against type, a lonely man whose family died in the September 11 attacks. In Reign Over Me, Charlie (Sandler) bumps into his old college roommate Alan (Don Cheadle) who slowly learns of Charlie’s sad story. The dramatic relationships are intelligently handed by director Mike Binder and the performances sprinkled with pathos.

Hollywood comedies have predictably taken the mickey out of post 9/11 airplane safety measures and passenger paranoia. Most recently, in Bridesmaids (2011), protagonist Annie (Kristen Wiig) gets high on prescription medicine and behaves loud and obnoxiously, starting a commotion that culminates with her being detained by an undercover air marshal.

In Due Date (2010), chubby loud-mouthed traveller Stu (Zach Galifianakis) mentions the word “terrorist” and “bomb” multiple times. He and businessman Peter (Robert Downey Jr.) are asked to come to the front of the plane. After some resistance an air marshal orders Peter to put down his Blackberry (“drop the device asshole!” ) then, when he deliberates, shoots him with a rubber bullet, receiving applause from the other passengers (including Stu).

Even Harold and Kumar had a crack in Harold & Kumar Escape from Guantanamo Bay (2008). Kumar smuggles pot and a smokeless bong onto a plane. An old lady sees him through the toilet door with a lighter and a funny looking device and screams “terrorist!” Harold tries to explain that it’s only a bong, but “bong” sounds an awful lot like “bomb” and the rest of the scene writes itself.

The reasons why Hollywood has stayed quiet on 9/11 are open to speculation.

One factor may be that studio executives don’t see the financial value of 9/11 movies. World Trade Center was far from a great performer at the box office — especially given the amount of free press and headlines it generated — earning a domestic gross of around US$70 million on a production budget of US$65 million. Reign Over Me was a considerable disappointment, with a domestic gross less than US$20 million (around the cost of its production budget) and United 93, while profitable, was never going to make a big splash.

Secondly, perhaps the right screenplays — the ones studio executives read, see dollar signs then fall over on their way to pick up the check book — haven’t been written yet or are currently in production. The Hurt Locker director Kathryn Bigelow was green-lit earlier this year for a film that focuses on US operatives’ ten year hunt for Osama bin Laden. It will incorporate scenes re-enacting (what we know of) his death in a Pakistani compound in May this year.

But the most pertinent factor is the nebulous nature of the war itself. The war on terrorism, as we know it, invokes a muddled sense of time and location. Its themes are both old and new and the enemy is impossible to relegate to a specific geographic area. The trickier enemies are to define, the harder they are to visualise.

Hollywood is known for many things. Nuance and complexity are not on the list.