Every serious change in the balance of offensive and defensive armament signals another sea of bloodletting, until some new balance is established making operations too dangerous to try. And then somebody executes on another idea, and off we go again.

The only thing that has ever stalled the gushing blood for long is commerce.

Uniquely, the cities of the Harappan culture in Pakistan and eastern India 5000+ years ago betray no hint of any military activity throughout their range, while wars of conquest raged in Mesopotamia.

Probably the Javelin missile could be made 10x cheaper and work just as well, but people don't want them to be that cheap.