New (World) Wars in The Late 21st Century

Many Nations had been trying to be the number one most powerful by declaring (World) Wars. The (World) Wars had been ignited thousands of years ago and it had been evolved in each period of time starting from the very first war till now. Basically, wars caused by the conflicts between tribes, religious or even cities in the ancient time. Since the world never stop developing, however, those conflicts become deeper and more sensitivity in terms of the contradiction which leads to the conflicts of interest as a whole.