Question

how did bronze age mark a shift from the new stone age

Answer 1

Stronger and more expensive weapons and armor meant a small, disciplined group of soldiers could absolutely dominate any less well-armed group they could march to meet. This put a tactical and strategic premium on organization over heroics. It made taking enemy as slaves a safer and more profitable option than slaughtering every man, woman, and child in the next valley. It meant everyone who had bronze technology had more in common with one another than with those stuck in the Neolithic mode, even if they were rivals. It made permanent class divisions not merely practical but militarily necessary. In short, it gave civilization the staying power it needed to grow and spread over a wide area.