This has already been said but I'm gonna say it anyway;
War has changed:
First there were rocks, then came swords, spears, bows and arrows, then came gunpowder and with them cannons and muskets, a few mechanical improvements and we have assault rifles. Tanks replaced cavalry and siege engines in one move. Airplanes replaced catapults and trebuchets and they too changed their payload from rocks to atom bombs.
War hasn't changed:
It is still fought by young men for the sake of some old men who spend too much time sitting on their arse thinking about numbers. It is still won by killing the other guy before he kills you. And the reasons never change, greed, hate, some bizzare sense of duty, politics, geopolitics, economics, they're all essentialy the same, take your pick.