General Discussion

War Is a Racket is a speech and a 1935 short book by Smedley D. Butler, a retired United States Marine Corps major general and two-time Medal of Honor recipient.[2][3] Based on his career military experience, Butler discusses how business interests commercially benefit from warfare.
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In War Is a Racket, Butler points to a variety of examples, mostly from World War I, where industrialists, whose operations were subsidized by public funding, were able to generate substantial profits, making money from mass human suffering.

The work is divided into five chapters:

War is a racket
Who makes the profits?
Who pays the bills?
How to smash this racket!
To hell with war!
It contains this summary:

War is a racket. It always has been. It is possibly the oldest, easily the most profitable, surely the most vicious. It is the only one international in scope. It is the only one in which the profits are reckoned in dollars and the losses in lives. A racket is best described, I believe, as something that is not what it seems to the majority of the people. Only a small "inside" group knows what it is about. It is conducted for the benefit of the very few, at the expense of the very many. Out of war a few people make huge fortunes.

https://en.wikipedia.org/wiki/War_Is_a_Racket