"Indeed our international order has been so successful that we take it as a given that great powers no longer fight world wars.
That the end of the Cold War lifted the shadow of nuclear Armageddon...that China and India remain on a path of remarkable growth," Obama said in his final address to the UN General Assembly here.
He said a quarter century after the end of the Cold war, the world is by many measures less violent and more prosperous than ever before yet the societies are filled with "uncertainty and unease and strife."
"Despite enormous progress, as people lose trust in institutions, governing becomes more difficult and tensions between nations become more quick to surface," he said.
He said that nations face a choice of pressing forward with a better model of cooperation and integration or "we can retreat into a world sharply divided and ultimately in conflict along age old lines of nation and tribe and race and religion."