I think few people like to go to war. (Correct me, if I'm wrong.) But wars happen non-the-less. What do you think why is that so? Who wants war and is able to force or convince others to go to war against their intentions for peace?
Or is there a "natural law" that describes a mechanism that war has to happen against all intentions?
If we know the mechanisms and/or plots of the warmongers, can we stop them?
Today I think most wars are due to resources and global/local influence. But it's not really easy to justify a war due to those alone, so normally you will have stuff like "we fight for freedom", "we fight for democracy and human rights." and what other excuse people will support, and in some cases this is also true or simply a covicident.
But war is business for a lot of people, a lot sell equipment, planes, ships etc. some get access to resources etc.
I think it's natural for humans to fight over natural resources and territories as it is for animals, if we are put in such situations. But I don't think war as we see it today is as natural as people would like them to be. Because again most of them is caused by ill intentions, which does not seem to be related to anything natural. But rather something that humans have created a demand for, because we are poor at communication and sharing stuff on a large scale.
Why people participate in wars, I think varies a lot, some might be "forced", others because they want to make a difference. Some might due it because of the excitement etc. I do however think that the military for the most part, is probably the ones that are most against having to use force and it is more the political game that end up starting them.
To stop wars from happening, I think it needs to be a political solution, countries have to figure out how to get along correctly and share with each other. The issue as I see it, is that there are so much money and influence involved in it, that it will probably not be easy. Politicians rarely listen to the average joe, unless they have a huge influential organisation behind them or lots of money.