The economic crisis happened because after years of economic prosperity, people started believing in the illusion that the economy will grow forever. This means that they started heavily borrowing and investing money from each other, and from this illusion, the economy became more and more inefficient as it (the supply) adapted to the people's illusions (the demand). Eventually, the investments were not making the returns that people expected, so the illusion was dispelled, which meant that unnecessary spending, investments, borrowing and lending was no longer justified. This meant that the inefficient economy was forced to become efficient. This means that a lot of it is "trimmed off", but this is talking about real people. These unemployed cannot find meaningful work, so the government feeds them to do meaningless work. Soon enough, the government realises that the ever efficient economy (with illusions dispelled) needs more resources. So the government now drafts the people doing the useless work into the army to obtain more resources for the economy. And then, it's war.
I'll expand a bit on the war later.
