Most of the violence that takes place on national scales (giving rise to wars) isn’t spontaneous. It tends to be planned. A question arises, then as to why people plan such violence.
Now the first reason as to why people plan violence on national scales is the desire to achieve certain political objectives. People have, for instance, been known to use violence to scare members of certain communities into voting in certain ways (or to scare them into desisting from voting altogether).
The second reason as to why people plan violence on national scales is the desire to attain certain economic objectives. One common objective is that of getting a market for weapons: as the folks who constitute the infamous military-industrial complex know that the demand for weapons is likely to go up greatly when there are wars. So, always remember, whenever you see a war taking place, that someone somewhere is benefiting financially. Such people then have the incentive to keep on fanning new wars, in order to keep the cash flowing into their coffers (regardless of human cost).
Folks who use plastic money in the form of, say, Citicards credit cards online at sites like www.citicards.com/login (which is the Citicards.com login page), or those who have other means of making payments online can use the same to pay for the various journal subscriptions. Those are journals where they can get more info on the politics and economics of violence.