I am not certain modern economies have failed to account for material, training, and maintenance in their military spending budgets. While, today, it appears military spending at least in the US is sustained at a very high level compared to other countries, looking closer reveals countries are spending about a comparable share of their gross domestic product (GDP) to the US with several ahead, notably Russian and that's only a mere 1% of her GDP.
From Forbes:
We may say Saudi is burning a lot of cash to support it's air war in Yemen and funding the Syrian insurgency. As we have no evidence Saudi boys are being called up to fight.
In the US, congressional districts vie for department of defense (DoD) dollars. A lot of that money is spent for supply, bases, training, and maintenance as well as procurement of new platforms.
We can see the Brits are in the same neighborhood as France, Turkey, and China.
I say, modern economies have learned from the past and have heeded the words of the US president Eisenhower in his famous "military-industrial complex" speech in 1961 before leaving the Orval Office making room for the new president Kennedy, he said:
"Until the latest of our world conflicts, the United States had no armaments industry. American makers of ploughshares could, with time and as required, make swords as well. But we can no longer risk emergency improvisation of national defense; we have been compelled to create a permanent armaments industry of vast proportions [my emphasis]."
NPR Staff ("Ike's Warning Of Military Expansion, 50 Years Later", January 17, 2011, http://www.npr.org/2011/01/17/132942...50-years-later)
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