Money; All war has money involved whether it's from the start or from half way through. Oil, some sort of resource comes into play no matter what. Your going to want to offer protection for the oil companies and the companies that have those resources so you can make cheaper trade for protecting them.
Power; Some but not all war is for power or the show that we are stronger. The 9/11 attacks on America showed that Al Queda has no fear of us. In our own hotheadedness we attacked back showing we have no fear of war and we control this our own way and will not be pushed around.
Religion Differences; Not alot of wars that involve America have this. But many middle eastern wars do. The ones that believe this land is our land and such over there own religious books but don't realize your just saying god in a different language. Isn't it not possible the two religions seen the same thing? Maybe different places different times.
Anyone else care to argue my points or just add to them?
Assassination is what caused WWI ; that's probably the only big one.
Assassination was the spark, but agressive nationalism was the real underlying cause of the war, from both sides. I guess that falls under BeyondKnights definition of power.
eeerrr... very small one but Passion(?) Helen "the face that launched a thousand ships" of Troy (yes a bit of a myth but whatever). There is at least one other but I can't remember it specifically right now. I suppose crime of passion could translate onto a larger scale.
Well, most of it issss caused by disagreements. yea thats it.
Assassination is what caused WWI
Uh I would have to say it goes earlier than that, when Serbia declared their independence from the austro-hungarian empire, that is when the war kind of started, it was the "balkan powder keg" that went off because of the "spark" as firefly put it. Because most countries gave away, what was called a "blank check" meaning that they would support the other country no matter what and unconditionally in any war, as a sign of good faith. So actually the WW was caused by the squandering of power.
Scandals... well, not what causes it, but what makes the wars heat up more.
welll.... They just heat stuff up, like Watergate. And maybe the beheading of some queens of england (henry the fourth I believe?) they just make the public riled, but not enough to create a war.
Unless... It was Helen of Troy, that is only instance, where it not only created a war, heated it up and made a ton of people pissed off at each other.
Fear tends to be at the root of a lot of misunderstanding. When people fear something, they often don't understand it or don't want to understand it. Then misunderstanding leads to distrust, which leads to enmity, which leads to anger, which leads to conflict. It's pretty easy to see how the negative qualities of the human personality are adaptations of fear. From a selfish perspective you can even define the good qualities of the human personality through fear. It is likely the most fundamental of emotions with roots that ground into the idea of self preservation.
I would have to say many different things cause it, with the most underlying cause would be the disagreements.
What the disagreement usually is the part that makes it different. Such as disagreements on how class systems should work and should the nobles really be on top. Disagreements on religious views, etc etc.
More than likely the main cause of war would be because of land and power. Let me elaborate. Land is a major cause of war because if a place wants more land then of course why not war. Back in the Han Dynasty's days war was always relevent. Everywhere you went you saw war. When the dynasty split into three Kindoms of which I cannot remeber there names started many, many non-ending wars for teritory. This of course tore the Han apart even more and the memory of the Han was vague. War had plagued the land all because of land. And power was largely involved in this war to claim the land of the Han. Being, like most people are, wanting to be the best and most powerful. This happened to spark many generations of wars for power and land. And this is mostly true today too. Take for instense the war in Isreal. The war is between the Isrealis and the Palistinians. This war was started because the need to take back the land of were their religions started. For the Isrealis it would be Judaism and the Palistines, Islam. This war is still going on as I write this post, rockets are being fired at the moment and killing innocent civilians. And of course some greed for power was also involved in this war. Thousands of people killed in the rise for land and power. Now, I don't really think that money is all involved in starting wars but once a war has begun, money becomes a large factor because of paying for damage, soldiers protection, ammunition, and propoganda. But that's just my opinion.
those three word are what your whole idea is around you did bring up modern things but besides in the middle east people don't fight over land and even that land is fought over because of religuse beliefs