[In a series critically re-examining a game released 12 months ago, our own Simon Parkin picks up Activision and Infinity Ward's Call Of Duty: Modern Warfare 2, to look at a single-player campaign "as memorable for its surrounding bluster as its actual content".]

Twelve months ago, no-one suspected that Modern Warfare 2 might be the final Call of Duty title created under the stewardship of series creators Vince Zampella and Jason West.

These two creative and business minds, now embroiled in a legal battle with former publisher Activision, grew the first person shooter series to its current, record-breaking popularity and, in their final game in the series, reached a critical and commercial highpoint.

Treyarch's Call of Duty: Black Ops may have claimed the spurious record of "biggest entertainment launch in history" last week, but that success is founded squarely upon on Infinity Ward's shoulders, who established and perfected the techniques that now define almost all contemporary military FPS blockbuster video games.

No game better exemplifies the strength and weaknesses of that format than Call of Duty: Modern Warfare 2, whose controversial level, 'No Russian', forced gaming's advocates to defend the medium not only to a watching world but also, perhaps for the first time in years, to themselves.

Mechanically, the game represents the most fully-formed realization of the modern FPS blockbuster, for better and for worse, from its linear level design, obfuscated by set-piece distractions, to the collectible intel files, 'hidden' inside rooms off the main corridors of each mission.

Beneath the bombast, it has everything in common with gaming's proto-shooter Space Invaders. You take cover behind walls before peeking out to shoot aliens. Twenty-two years ago the aliens were line-dancing extra terrestrials. In 2009 they were Afghans. The metaphor changed, but the principle remains the same: avoid missing headshot for high score.

Likewise, the opening shooting gallery training level that takes place on a desert encampment, soldiers idling in the heat and dust while you sprint from pop-up target to target, is a 2009 rendering of Duck Hunt, the final evolution of a medium that has always obsessed over bullets and targets. For that reason, despite the visual firework display and cacophony of barked orders, play can feel curiously one note and familiar.

Guns are the sole mode of player reach into the world, not solely because of the contemporary military setting, but also because this point and click tool continues to be the most efficient way to allow a player to interact instantaneously with a virtual world both near and far.

Down the barrel of Call of Duty: Modern Warfare 2's guns, you can snipe a soldier two miles away, before using its butt to knock out a guard 2 feet away. The weight and feel of these tools is here perfected, while, in the game's most controversial level, the gross limitation of that sole verb they offer the player, 'shoot', is clearly revealed.

It's here, the game's most talked about moment, that you accompany a group of terrorists as they mow down unarmed civilians in a Russian airport. While you have the choice to skip the level entirely, once in it, you ride on a conveyor belt through the hellish fairground ride, your only choice to shoot, or not to shoot.

The removal of meaningful choice for the player is both frustrating and (perhaps unintentionally) brilliant: through it, the limitations of the first-person-shooter's purpose and themes are revealed. For years this brand of video game has limited interactions to destructive ones fired down the barrel of a gun. In this moment, we wish for a bandage.

But perhaps the loudest message 'No Russian' spoke was of cinematic gaming's frequent inability to maintain a consistent tone and voice. While the game may know exactly what it is in terms of its systems, in terms of its scenario it's a confused confluence of approaches.

It opens with a step for step tribute to David Simon's Generation Kill, sharing camera angles and composition with the second episode from the HBO drama. You must protect a bridge before crossing it in a Humvee, leading into a tense creep through a hostile city, scanning rooftops and doorways for potential threats, the order "Do Not Fire Unless Fired Upon" still ringing in your ears.

This grave approximation of gritty drama/ Six o' Clock News is then juxtaposed with the second level, which has you tearing across a snowscape in a snowmobile, firing from the hip and leaping ravines in a James Bond-esque white knuckle-ride. Then there's the airport massacre, a po-faced rendering of snuff CCTV footage entirely out of keeping with what has gone before.

The tone and approach continues to veer left and right, soft and hard as you work through American suburbia like a Rainbow Six CQB soldier one moment, before storming the ruins of the White House as it burns against a black fire sky the next.

As a result the game's abiding message is confused. Try to remember the experience 12 months on, and you'll recall diverse set pieces, tied together only by way of the mechanics they clothe. Perhaps this is the point. Modern Warfare 2, and its legions of impersonators, offer a Disneyland tour of scenarios, an exhilarating parade of scenes and feelings that do little to educate or enrich in the long term.

And that's entirely reasonable. Video games are entertainment and not every title should be forced to display ambition that stretches further than popcorn thrills. But in 'No Russian's attempt to offer more than mere happy distraction, the inability of this linear roller-coaster ride FPS to sustain wider commentary is made clear.

A year on, a moment touted by many as gaming's most compelling stab at maturity, is as much memorable for its surrounding bluster as its actual content. It's arguably a criticism that can reasonably be leveled at the wider game it's part of.