It’s the collection of business people who profit from selling goods and services to military. They have corporations, companies, and even small business that provide for the military. Companies that produce ships, airplanes, tanks, other military vehicles, all their parts, missiles, ammunition, dresses, shoes, rations, communication devices, toilets, tents, computers, software, etc.

There are also academicians who work for them. Journalists who fork for them. Politicians who works for them. Intelligence organization personnel, judges, prosecutors, lawyers, etc. all who work for them officially or clandestinely.

All these people comprise a social network like a “state”. They actively push for policies that would result in more military spending.