I suppose war creates resilience in people to live with less and make do. That head-strong mentality helps a lot.
What is left over is indeed a resilient population, but that's nowhere near enough to (re)build a country.
Why stay behind to rebuild when you can move to Holland or Austria?
That's why waging a war always needs some decent rebuild plan, similar to WW2's Marshall Plan. Never thinking further than "throw a shitload of money towards military contractors, NGOs and whoever we can find willing to serve as a government" is what led to the failed states of Afghanistan, Iraq and Libya.
If the West had offered the people in these countries the clear offer "we give you X billion dollars, in exchange for actual democracy and stability", the results would have been way different...
I would love it if we could bribe our way to a more peaceful world, but I don't think it's that easy.
Not his fault he grew up in a country the rest of the world thought they were taking advantage of.