I always interprated it as being about how no one is completely good; everyone has the potential to commit grossly evil acts if subjected to the right circumstances, and thus the Viet Cong are neither better nor worse than the Americans.
I seem to remember that what he says is something like they were moral enough to give them the right kind of motivation but immoral enough to be sufficiently ruthless to get the job done. In that context all "moral" really means is "motivated by their own morals", and that kind of balance can, I'm sure, be useful in warfare.
It's vital to note that the US never occupied North Vietnam, nor had any intention of doing so, just removing them from South Vietnam and maintaining its freedom.
It's also important to remember that Kurtz is batshit insane.
I always thought that the point Colonel Kurtz was getting at was that in warfare it is insane to be placing objective morality of right and wrong on the battlefield where the point of war has and always will be to murder each other until one side is destroyed or gives up, petty preconceptions of morality shouldn't exist in war. The Vietcong and the NVA were willing to do WHATEVER it took to achieve victory regardless of the morality of their actions and didn't let "judgment" based on those societal/moral preconceptions defeat them; the Americans weren't and that is why Kurtz felt that they were eventually going to lose the war. Americans were nowhere near as dedicated as their enemy. We may have been vastly more well-equipped than our enemy but to us it was just a matter of containment based on the larger Cold War—for the Vietcong/NVA, getting rid of the Americans was a matter of life and death to which they were willing to dedicate every last man, woman and child to defeat. Had America given such dedication the war would have been over in just a few short years. Kurtz realized that it is important to be a moral, good-natured person but at the same time be able to tap into your instincts and kill the enemy without passion, judgement or remorse, because that is how wars are won. Kurtz isn't insane, he is just realistic about how harsh war is and how harsh you have to be in return to win a war.
The above seems to be the most substantiated interpretation, as Kurtz places great emphasis on the fact that the Vietcong are motivated to commit horrible acts out of the deep love they have for their families.
Important to note is that the US was not oppressing North Vietnam, just trying to keep South Vietnam free from North Vietnam. Additionally, accidents happen in war, and there are always rotten apples in every military. Furthermore, the highly publicised and famous friendly fire incidents involved ARVN troops, not US.
No, the US dropped thousands of tonnes of bombs on North Vietnam, and the most famous war crimes of the war—including the My Lai Massacre—were indeed committed by US troops. The US played dirty, and it can be argued they played much, much dirtier than North Vietnam because they intruded on a civil war they were never asked to be in. They were just in it to stop the communism spreading—which didn't happen anyway—and killed millions in the process.
With all due respect, My Lai was a mere preschool playground spat compared to the atrocities committed by the North Vietnamese/Viet Cong. The best words ever stated on this issue was on the now-defunct A List (celebrity gossip) website when it chastised Jane Fonda: "We [the U.S.] sure weren't saints during that [Vietnam] war, but the North Vietnamese and Chinese were a damn sight worse."
Leaving aside the issue of atrocities, the USA started out by sending dozens, then hundreds, then thousands of 'military advisors' to Vietnam, as part of its own ideological campaign to "contain the spread of Communism", even though that meant interfering with the affairs of a foreign country. Vietnam was only partitioned in the first place because the communists had occupied the North and the French were occupying the South for colonial reasons; when the French were defeated the Americans entered the country in what, when any other nation does it, is described by America as an "invasion". The Americans were hostile troops occupying a country that didn't want them; in short, they were the bad guys, and the good guys won when the Americans were driven out. If you want proof, consider that Vietnam today is not a totalitarian hellhole like North Korea. Its human rights record is far from perfect, but since the passing of post-9/11 anti-terrorist laws prohibiting assembly and authorising wiretaps, so is the USA's. Vietnam is a growing country with a healthy economy, and most of its problems are due to the legacy of the occupation.
It always bothered me why U.S Command sent a recently divorced and clearly traumatized veteran of the currently ongoing Vietnam War on a top-secret mission to kill a rogue U.S Special Forces Colonel. You would think they would choose another Special Forces guy who didn't have all these psychological issues to take the mission. Then I realized that the concept of post-traumatic stress disorder was only recently coming into the limelight at that point, and before that, most military forces around the world didn't care if you were traumatized by what you experienced—if your body was intact and you could fire a gun, you were good to go. The U.S. military would be no different towards Captain Willard.
If they kept him, he would be nothing but trouble. If they sent him, he would kill the Colonel or get killed himself. Either way, one less problem
It seemed more like they were fighting fire with fire, by sending a mentally unbalanced individual to assassinate an insane, rogue colonel.
This is definitely true. By 1969 the U.S. military was taking anyone willing to wear the uniform; if it wasn't for the war, they wouldn't have looked twice at men like William Calley. It also makes a certain amount of thematic sense to send Willard to hunt down Kurtz; Kurtz is what Willard has the potential to become.
Actually, there was nothing about Calley, prior to joining the Army that suggested the atrocity he would ultimately order.
For the longest time I thought the part right before the crew enters Cambodia past that bridge was surreal just for the sake of being surreal. Then I realized that we are looking through the eyes and ears of Private Lance who is currently stoned on drugs, no wonder it was surreal.
While the plot of Apocalypse Now is essentially Conrad's Heart of Darkness, most of the scenes are taken nearly verbatim from a real-life, first person account of the war, whose title I alas cannot remember. The scene at the bridge is exactly as described, right down to the stoned-out M79 gunner killing the screaming VC with a single, instinctive shot in the dark. The movie was surreal because the war was surreal.
Colonel Kurtz's assassination turns out being for nothing in the long run. The entire reason Willard was contracted to kill Kurtz was so that his methods of fighting in Laos and Cambodia would be kept secret as America wasn't supposed to be there, even though that type of tactic would be beneficial towards achieving victory. America ends up leaving Vietnam, giving up on winning the war, and the presence of MACV-SOG and the CIA's top secret missions going on there end up being revealed after the end of the war anyway. The death of Kurtz covered up nothing. Kurtz had practical military necessity in mind, not his commanders. A model officer and a loving father and husband was killed for no real reason.
The real fridge horror sets in when you realize we need people like Kurtz to make war, and still manage to think war is something that should be done.
Kurtz's death actually is a good comparison for every soldier that died during the Vietnam War. America ended up losing the war when they finally gave up on achieving victory and went home. The Vietnam War was a meaningless war and all of our objectives failed. The lives of 58,000 men were wasted. Men like Kurtz did what was necessary to win, but since their commanders were not willing to take that extra step, men like him ended up having their lives wasted. The public reception to the Vietnam War was bad enough—now imagine if the public knew we had killed one of our own for a war that ended up failing anyway. It would be a public-relations disaster for the U.S. military. Yet "[doing] what was necessary" to win the war would've meant Jumping Off the Slippery Slope, crossing the Moral Event Horizon, etc. Call it what you like: Kurtz was not meant to be admired for his actions. He became a monster because he saw it as the only way to fight equal monsters. the resolve to "[do] what was necessary" was irrelevant in deciding the outcome of the war. The Tet Offensive effectively destroyed the Vietcong's ability to put up a resistance, but the perception of the attacks was that despite all the work done thus far, nowhere in South Vietnam was safe from NVA/VC attack.
Would one Colonel, no matter how charismatic and skilled, really be enough to disrupt the effort of a war machine as powerful as the American military? The Generals seem to think that Colonel Kurtz is a threat to their operations, but the only thing Kurtz' overt actions are going to reveal is that America has a presence in Laos and Cambodia when they are only supposed to be operating in Vietnam. At worst the Communists will just get a little angrier than they already are, but who gives a shit? They hate you and want you out of their territory already so it isn't like one Colonel is really going to make a difference. Besides what makes the whole affair even more pointless is that the Vietnam War didn't even end in our favor, the death of Colonel Kurtz was entirely irrelevant in the long run!
Part of the theme; the generals aren't overtly crazy like Kurtz is, but nobody involved is completely correct, right, or sane.
The voiceover seems to imply that it's at least partially an ego thing - Kurtz is making the US Army look bad because his tactics are more effective than theirs.