Will they ever learn?

Unfortunately... never.

Today, on the 100th anniversary of the end of the First World War (I systematically refuse to call it the "great" war), Luca and Finn actually enjoyed today's forest walk because they spent the whole time shooting at each other, with a bilaterally imagined but varied and detailed arsenal of hand guns, semi-automatic weapons and other RPGs. 
For the record, the girls did not take part in the role playing.
For wars are mostly waged by gullible testosterone-fuelled young men, commanded by older men who had kids from trophy wives on the verge of their senile years. 
Because anyone with a fraction of a notion of an idea of what it takes to not just conceive kids but also help them grow to their full potential would think twice before sending them running towards barbed wire and fully functioning machine guns... 
A mother never would. 
An ageing general from the inbred aristocracy with a total disrespect for 18 year old male peasants would... 

Then again, since the advent of the nuke and its global annihilation capability, we have not witnessed a mass conflict for the longest known period in history. 

The few localised genocides in Rwanda, the Balkans, East Timor or Sudan only barely counterbalance the fact that for the last half century, we have not had a single population-regulating conflict.

For war, and killing, have been a constant since the dawn of humanity. 

The nuke has disrupted the bloody and precarious equilibrium. 
We are living in a very very very very very tiny sliver of exception in the continuum of history. 

All the signs are in place to remind us that this freak experiment will be short-lived. 

Shite, I'm turning into 'youroneindoors…