The problem is that the water and energy aren't where the users want it to be.
But pipes are relatively cheap - if humanity cared enough, we could build pipes to distribute the plentiful water everywhere.
But it turns out the people without much water tend to be in very poor places and warzones where there isn't much appetite for spending money on pipes.
Why on earth is this the top post?
Wait till you learn about the people they are fighting....