“I face the world as it is,” President Barack Obama said this month, accepting the Nobel Peace Prize, “and cannot stand idle in the face of threats to the American people. For make no mistake: Evil does exist in the world.”

The tenor of this speech, which coincided with Obama’s decision to send 30,000 more troops to Afghanistan, suggests a leader who must explain a war while being feted for peace. As the title of one seasonal multiplex diversion, opening this week, puts it: It’s complicated.

Who knows? Perhaps Obama’s Bushian hawkish phrases were provoked by something as simple as seeing the wrong in-flight movie on Air Force One, en route from D.C. to Norway. Perhaps Obama finally caught up with “Transformers: Revenge of the Fallen”? If so, surely he was rankled by that blockbuster’s implication that our country is being run by a symbol of mealy-mouthed appeasement. Obama is mentioned by name in “Transformers 2” though his face remains off-screen. He is the chump trying to negotiate with the enemy.

You can like “Transformers 2” or not like it, or in fact, hate it. But you cannot dispute its politics. It may strike an apolitical pose (it is, after all, about robots from space), yet it hammers home the box office-tested belief in U.S. military firepower conquering all. The Middle East is a plaything to be destroyed in director Michael Bay’s universe. Why even go there if you can’t destroy a pyramid?

Compare that film with “Avatar,” likely the most expensive film ever made. Thanks to its dazzling melange of digital effects and immersive 3-D visions, many (including Steven Spielberg) have called James Cameron’s eco-destructo fable the future of the medium. Cameron, as we know from “Aliens,” “Terminator 2” and “True Lies,” among others, is a maniac for instruments of war and their highly cinematic destructive possibilities. Yet he agitates for peace in his fables. As such, “Avatar” combines a strange and unruly series of messages about colonialist venality and might making not right, but wrong.

The story’s about a paraplegic ex-Marine trying to serve two masters on the distant moon of Pandora. His first master is a tough­love research scientist whose avatar program allows humans to enter a virtual-reality state and inhabit the minds and, in effect, the bodies of their10-foot-tall surrogates, who mix and mingle with the Pandoran natives.

The Na’vi are good, clean-living folk, and they must be eradicated if the occupying force’s strategic mission is to be successful. Jake, the soldier, agrees to spy on the Na’vi for the increasingly monomaniacal security chief played by Stephen Lang.

While many fables across the centuries have dealt with the tantalizing concept of “going native” and questioning or refuting one’s allies in a time of slaughter, “Avatar” is the first to do so while making its goggles­wearing audience (it’s also available in regu­lar 2-D) collectively gasp: “Wow. Cool! I mean, wait, that’s tragic! But it’s cool!” Though Cameron freely samples all sorts of genocidal history, with a visual and thematic emphasis on the Native American’s loss of the West, the movie’s parallels lie most explicitly with the war in Iraq. Cameron’s dialogue includes references to “shock and awe” and “fighting terror with terror” and at one point there’s a grieving close-up of an enraged Na’vi woman, her village destroyed by American firepower, ululating a war cry (!), while our ex-Marine hero steels himself for what comes next.

If you want to read “Avatar” politically, and certainly most people won’t, it’s a movie that questions any occupying force’s actions, be the natives red, white or, in this case, blue.

Cameron’s parallels to the Iraq occupation barely make sense, and when they do, they’re incredibly ham-handed. Will they have an effect on the film’s undeniable “Wow! Cool!” factor at the gate? I doubt it. Like many other Hollywood phenomena, it’s probably too good-looking, too cinematically alive, to fail.

In the middle of these two hammering blockbusters, one right-wing, one sort-of-left, lies a film of very different intentions and genuine political complexity. “The Hurt Locker” was made by director Kathryn Bigelow (who happens to be Cameron’s former wife). It is set in 2004 Iraq, and the story is a procedural about bomb detonation experts up against it, hour by hour, day by day. It is harrowing, and it has grossed about $16 million worldwide, a small fraction of “Transformers 2” or “Avatar.”

“The Hurt Locker” is also the most honored American picture of 2009, to date. (“Up in the Air” is a close second, and to me feels like the front-runner in the forthcoming Oscar race.) Its reputation continues to grow.

And in its depiction of a brave, reckless, provocatively complex warrior, played by the excellent Jeremy Renner, “The Hurt Locker” was the one war-suffused film of 2009 that bridged the political divide, simply by avoiding polemics and sticking to the horrifying workaday details. Its primary character is a young man forged by war, increasingly unable to cope without it.

War is a drug, as the opening quotation tells us. Diversionary entertainments such as “Transformers 2” and “Avatar” are drugs as well, the second one having the considerable advantage of spatially coherent, rhythmically dynamic action sequences. Both, however, are designed to rev us up on destruction and payback (and, in the Cameron film’s more intricate case, the price of loyalty above humanity).

The screen fights our battles, over and over, and we’re left with the strung-out sensation of wondering how much virtual fun we should be having with these scenarios.

And then we lock and load for more.