Once upon a time, war was a predator. Back then, warfare, as Clausewitz said, was
...not merely an act of policy but a true political instrument, a continuation of political intercourse carried on with other means.
Now, of course, political policy is a limited thing. It's limited in terms of both goal and time. Once the aggressor in a Clausewtiz style war is appeased, once he has eaten his full, his interest in the war is over. That's the way it used to be.
Today, things are a little different.
Today, war is a parasite. It exists not as an instrument of political coercion, but as an economic tool; and economics, unlike politics, has no limit except that of greed.
Once upon a time, war profiteers used to hang around the margins of a conflict ordered by kings and generals. Today, war is an industry run for a profit.
Now, there's a very fundamental difference between the goals of a predator and a parasite. For a predator, it's essential to capture its prey (and secure its meal) with a minimum expenditure of time and energy. It is successful when it can deal out a swift kill, satisfy its hunger, and leave.
For a parasite, though, a swift kill - or any kill, for that matter - would be disastrous. A successful parasite is one which keeps its host alive, so that it can keep providing said parasite with everything that it needs. The host will be sick, debilitated, and hurting; but it will not be allowed to lie down and die, because, when it does, the parasite dies, too.
During the great wars of earlier times, like say the First World War, armies were rapidly expanded and weapons manufactured, but once peace returned those armies were sent home and the surplus weapons scrapped. Of course, as Smedley Butler said, war was a racket, but it was a racket which functioned in fits and starts, because it wasn't an industry. Today, it is.
Today, the rationale of war is profit, from the seizing of resources to the continuous manufacture and consumption of weaponry and ordnance. The arms industry is no longer something which goes into hibernation between conflicts; it is something which creates and perpetuates conflicts. The media, the entertainment industry, the stock market (what with all the armament and reconstruction shares on offer) all have become part of the war industry, and therefore have a vested interest in keeping it going.
Biological parasites, actually, are far more horrifying in their effects on their hosts than predators are. The war industry is no different.
Today, everyone but the war industry are victims, part of the host as it were. The people whose taxes fund the armament industry, the soldiers who fight for wars not their own, the civilians who are converted into “collateral damage”, they are all victims. Everyone suffers and everyone dies, but the host lives on.
Rather than a means to an end, war has become an end in itself. Remember how they called the First World War the war that would end all wars?
We know how that turned out, and also we know why.