Since its inception, movies have starred the beautiful people. Young people. The kind of people you simply wouldn't see on every street corner. It's such a Hollywood cliche to discuss the film industry chewing up young stars and spitting them back out once they start to get up there in years, but it's only a cliche because it's happened enough times to take on truth.

But, there have been times in cinematic history where youth and beauty have taken a backseat to age age and experience. Every so often, we stop caring about traditional movie stars and start embracing something the folks who look like they've taken a beating. Sometimes, the older folks start to take over the spotlight and right now, we're living in the age of the Old Man Action Hero.

But why now?

The Old Man Action Hero: Wherein older, sometimes borderline geriatric men, usually armed to the teeth, act in movies where they kill as many people as humanly possible. Sometimes, their age is treated as a the crux of a central joke (like Bruce Willis in 'Red'), but most of the time, their age is treated as their greatest attribute, the aspect of their character that commands and demands the most respect. We're not talking about middle-aged but eternally youthful actors like Johnny Depp and Tom Cruise, who have shrugged off age like an annoying fly and won't actually play "old" until their metabolisms ultimately betray them. We're talking about the guys whose faces showcase a lifetime of decisions and whose bodies display a lifetime of abuse.

You can't help but admire the hell out of the generation that had their mettle tested in the fires of war and came out wisecracking, casually badass motherf---ers.

Here's the important thing to remember about the Austrian Oak and Sly: they didn't come to this whole action hero thing late in life. They were play violent, over-the-top action icons when they were young men, their preposterous physiques and undeniable charisma making them perfect icons for the macho, testosterone culture of '80s America. They were a new era of movie gods, far removed from Bogart and Peck. And then the inevitable happened: they got old and people stopped going to their movies.

A lot of things happened after that - some pretty amazing (governorship!) and some just plain sad ('Driven') - that indicated their careers as movie stars were all but over. Finished. But, we know what happened next: Stallone staged the comeback to end all comebacks with 'Rocky Balboa' and 'Rambo.' Schwarzenegger left political life and came back to the movies without missing a beat (uneven box office or not, he's booked solid for the next few years). The two of them share the screen in the wildly successful 'Expendables' franchise, which has only added more and more past-their-prime action stars with each entry.

It's easy to call their comeback an act of pure vanity (and it is). It's easy to say that the popularity of some of their newer films can be laid entirely at the feet of blind nostalgia from their fans (and that's also true to some extent). But what's most fascinating about our age of the Old Man Action Hero is that Schwarzenegger and Stallone aren't the ones spearheading this particular renaissance. In fact, they're playing second fiddle to a guy who, in his youth, was rarely ever an action hero.

Enter Liam Neeson. In 'Taken,' 'Taken 2,' 'Unknown,' 'The A-Team' and the upcoming 'Non-Stop,' the man who once starred in 'Schindler's List' is re-imagined as a gun-toting killing machine, an unstoppable badass who murders his way across the world to save the day (and by day, we mean daughter). Unlike Sly and Arnie, Neeson isn't chasing his glory days. He isn't reigniting childhood fandom and passions. He's carved an action career for himself at the age of 62, after decades of taking on generally quieter and human roles. Neeson is evidence that the Old Man Action hero isn't just a nostalgia thing -- it's a cultural thing. It's not going away either. What else is Kevin Costner's '3 Days to Kill' if not an attempt to grab onto Neeson's coattails?

So, why would the current generation of moviegoers embrace a bunch older tough guys while movies starring younger, prettier people fall by the wayside? Enter one crazy theory: because of World War II.

Anyone with a grandparent (or anyone who paid attention during history class) knows a thing or two about the largest mass-conflict in human history and the brave men who fought in it. These are men who are so fearless they became known as the Greatest Generation. We're talking about soldiers who literally travelled the globe eradicating evil, developed the world's thickest skin and proceeded to go home and have millions of babies who grew up hearing of their exploits. With the rise of television, mass media and the counter-culture movement, the true nature of war erased any romanticism that could have built up around the conflict in Vietnam and the "War on Terror" has always existed in various shades of gray. For millions of Americans (particularly those under 30), World War II feels like the last time America went to war for a truly just and good reason, making the people who fought in it the last generation of True American Heroes.

The reality of it all isn't as black and white as that (stories of WWII vets coming home with PTSD were hidden from the public eye), but perception is key. Generation X-ers and Millennials are generally more than happy to protest from behind a username and enjoy the luxuries that modern technology have afforded us, but there's still a sense that we're lesser people than our grandfathers. There's a reason the popular "Overly Manly Man" meme exists and is usually quoting grandfathers: the modern American male can't help but think he's less tough and can't help but admire the hell out of the generation that had their mettle tested in the fires of war and came out wisecracking, casually badass motherf---ers.

Perhaps it's a crackpot theory to think that we love Liam Neeson in 'Taken' because he reminds of our grandfathers and great grandfathers. After all, Neeson, Stallone and Schwarzenegger are technically Baby Boomers who only resemble their parents' generation when in front of a camera. Maybe we need some more time. But right now, it looks like a transitional generation celebrating the last truly brave generation, almost as an act of mourning. When the old guys are gone, who are we going to look to next? Because there don't seem to be too many heroes who are our age.

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