Of all the enemies Rambo has faced down over an almost 50-year rampage through pop culture, it's those critics who dismiss him as a two-dimensional action hero who are his real nemeses.
Then again, being misunderstood has been the entire key to Rambo's survival all this time.
With Friday's release of "Rambo: Last Blood," Sylvester Stallone returns to play the haunted veteran who cannot seem to avoid killing no matter how hard he tries to be left alone, this time battling a violent Mexican cartel that kidnapped his beloved niece. Whether it's sex traffickers or Soviet soldiers or intolerant small-town police, Rambo remains a sympathetic underdog for many moviegoers regardless of the body count left in his wake.
"I think (he resonates) because Rambo is not this 'monster at heart,' he is actually a discarded human being," Stallone told NBC News by email ahead of the release of the franchise's fifth installment.
"(He's) someone who was left behind; who did a job he was asked to do and now he is held at arm’s distance away from ever being embraced by the country he loves so much.
"So he is feeling very, very rejected — which I believe many people (also feel)."
The new movie is the latest salvo in a continuing campaign that started with the 1972 novel, "First Blood," and continued with the movie adaptation 10 years later — the first film in the franchise has earned $728 million globally at the box office to date.
But even Rambo's biggest fans can't agree on why he's lasted this long. He's been seen both as a liberal rebuke against a conservative society and a Reagan-era champion against communism; a harmful stereotype to some veterans and a cathartic symbol of how the country has unfairly treated its soldiers to others.
“I’m almost a political atheist. I’m not a political animal and I never wanted to be," Stallone told an audience at the Cannes Film Festival in May. "I just thought, this is an interesting story about alienation."
“But, oh my God, once President Reagan went, ‘I saw Rambo, and he’s a Republican!'"Stallone, added, dropping his mic to the amusement of the crowd.
Despite an image as a red-meat-and-potatoes American hero since the release of the 1985 sequel, "Rambo: First Blood Part II," Rambo has proved more analogous to tofu — taking on the flavor of the observer's personal tastes.
"He's always been a litmus test for people's personal politics," author David Morrell said. "People see what they want to see."
Morrell should know: He dreamed up the character. As a Canadian graduate student working on a doctorate in literature at Penn State in the late '60s, he witnessed the generation schism that rocked his adoptive country over the Vietnam War. The assassinations of Martin Luther King Jr. and Robert Kennedy; the Tet Offensive; the chaos at the Democratic Convention in Chicago: it all felt to him like the front lines had moved to this side of the Pacific.
So he came up with the allegory of pitting a Medal of Combat recipient home from Vietnam and struggling with post-traumatic stress disorder against a small-town southern police chief, himself a distinguished veteran of the Korean War, who mistakes him for a vagrant. The simple misunderstanding leads to a showdown that leaves dozens dead and dooms them both.
The result was a literary sensation: "First Blood" has never been out of print in the 47 years, and it's been translated into 30 languages and taught in classrooms. It took a decade, but Rambo eventually made it to the big screen. With Stallone, the perfect combination of the physicality needed for his role and box office sheen from the first two "Rocky" movies, in the title role, the movie toned down the body count and made Rambo less of an anti-hero.
Morrell said the popularity of the book and the film helped change the way the American public, particularly those who opposed the war, viewed members of the armed forces. "I watched the way service people returning from wars were treated subsequently," he said, "and I think that the film helped persuade audiences to see unpopular wars as having people who create the wars and others who are forced to fight them."
But advocate Paul Rieckhoff, himself a veteran of the Iraq War and host of the "Angry Americans" podcast, says Rambo is not a hero to a large number of vets.
"Unfortunately for an entire generation, it defined the identity of a Vietnam veteran," Rieckhoff said. "In the community, we literally call it, 'The Rambo Stereotype.'"
"We are often trying to combat the image of the broken, damaged violent person."
It's an image also perpetuated in other Vietnam War movies of the late '70s and the early '80s, including "The Deer Hunter" and "Apocalypse Now."
The broken, emotionally damaged Rambo was originally sentenced to die in the climax of "First Blood," but test audiences hated that ending, Morrell said. So, director Ted Kotcheff shot a new one that kept the troubled hero alive in the version that hit theaters in 1982. The filmmakers weren't considering sequels at the time, but the critical and box office receipts meant Stallone and his onscreen alter ego would be conscripted for a second mission in 1985.
A very different mission.
Fresh off Stallone's success in the Cold-War themed "Rocky IV," this shirtless version of Rambo would be sent back to Vietnam to save a band of prisoners of war asking his superior, "Do we get to win this time?" Not exactly an anti-war allegory.
Suddenly, Rambo became a conservative icon, a hero name-checked by then-President Reagan when discussing what he would do in the event of another Iranian hostage crisis. “Boy, after seeing ‘Rambo’ last night, I know what to do the next time this happens,” he said at the time.
That version continued with the third movie, "Rambo III," three years later, which pit the hero against the Russians in Afghanistan. Many critics consider it the nadir of the franchise.
"There was a lot of enthusiasm for all things Stallone in the 1980s," Christian Toto, founder of HollywoodInToto.com, said. "As a conservative critic, those movies symbolized the American dream, rooting for the underdog, and was mostly tied into the Reagan era."
But even then, Rambo was not that easy to classify. On a publicity tour in Poland in 2001, Morrell was surprised to find his visit splashed on the front pages of newspapers. He asked a local journalist, a woman in her 30s, about the headlines.
"She told me that during the Solidarity years, the Rambo movies were illegal in Poland, but they were smuggled in," Morrell recalled. "People would watch these films, put on a bandana and went out to demonstrate against the Soviets."
"The woman said, 'In an indirect way, your character helped bring down the Soviet Union.'"
In 2008, Stallone brought his character back to the multiplex for a fourth time with "Rambo," which returned the character to the haunted outcast he was in the first movie, this time against sadistic guerrillas in Myanmar. It proved a box office disappointment.
Now, he's back for a fifth tour of duty with "Rambo: Last Blood." The movie may open with Rambo enjoying domestic bliss on his family ranch in Arizona, but it doesn't take long for him to go back to working out his anger management issues in gory fashion. "I haven't changed," he tells his niece during the calm before the storm. "I just put a lid on it."
When that lid pops off, he could earn the Guinness world record for Geneva Convention violations he performs on the army of bad hombres.
Is the strong, silent hero making a political statement?
"The cartels seems like a bullet-proof villain, no one is going to defend drug dealers," movie historian Peter Biskind said. "But anytime you use Mexicans as villains in the Trump era, it could be seen in the context of Trump administration policy."
Stallone, though, seems convinced that his second most famous role transcends labels: "That inside, beneath the brutal exterior and the exploits, (he) is really a man-child," the actor said of Rambo's appeal. "Someone who has just lived in the shadow of rejection and is still willing to help people, to sacrifice himself for a cause."