Enlightened self interest doesn't work on a scale necessary for a civilization to function.

Every nation that has next to no government and every man is free to do with his life as he wishes is a giant shithole that teeters in and out of revolution. Want to see objectivism at work? Go visit Somalia or the Democratic Republic of the Congo. In those countries every man is free to pursue "... his own happiness as the moral purpose of his life, with productive achievement as his noblest activity, and reason as his only absolute." Countries full of people who are "all noble heros free to pursue their dreams". Too bad their dreams all involve mass murder and slavery to pursue personal wealth and power.

Hobbes was smarter than Rand. We have a Government to protect us from each other.