Post-war economy in fiat money era

What happens to the economies of countries ravaged by war, facing large scale destruction?

Paradoxically, economies often expand rapidly.

Huge economic space is created in those counties, from the destruction of wars - the space to build modern infrastructure, deploy all the available human resources and produce real wealth, the goods and services.

Money enables that in the fiat era, as it is issued without any intrinsic value - that is, not backed by anything valuable as it was during the gold standard and a national currency gets all its value from what it produces and is available to buy.

https://papers.ssrn.com/sol3/papers.cfm?abstract_id=6510061