What's both very strange and interesting about Ukraine and the war there

I remember as a child being shown may pictures and movies of towns in Europe and Japan and Russia being leveled by warfare and piles of bodies various places sometimes 1000 people deep. They showed these things to us even though many were traumatized by this as a way of preventing another World War at sometime in our future when we all grew up. I was born just after World War II ended by the way. So, there were many men (and women) around who had been driven insane by World WAr II in various ways. So, as a child you had to watch out for crazy people from world war II or they might beat you up, knife you or shoot you or kill you. And this sort of thing happened a lot still until around 1960 or so when most really messed up people had either been shot by the police or themselves or a family member by then. And then to a much lesser degree this also happened during and after the Viet Nam War too.

What I find interesting in a strange way about the war in Ukraine is that Putin is destroying everything above ground in cities like Mariupol and others.

But, the other thing I know is that Earth might house as many as 13 to 14 billion people if everyone lived underground instead of on the surface. Why?

Because if you tear down all the cities and then all the land becomes farmland or recreation land and you could actually house and feed up to 13 to 14 billion people then.

But, if you leave cities and homes like they are or build more then only 1 billion people can live on the planet for thousands of years.

So, there is a choice here folks of how many humans can live on the planet 1 billion or 13 or 14 billion.

And up until now we have made the choice by all our actions that only 1 billion can live on the planet for thousands of years. 

However, by leveling Ukraine Putin is driving everyone underground so they don't die from cluster bombs or little metal darts which are another form of cluster bombs hitting everywhere now too.

Don't you find it strange that Putin is forcing everyone in these cities to live underground when that could be a solution to more people surviving for thousands of years here on earth?