Steven Pinker ponders it in an interview with Scientific American:
I suspect that violence against women, the criminalization of homosexuality, the use of capital punishment, the callous treatment of animals on farms, corporal punishment of children, and other violent social practices will continue to decline, based on the fact that worldwide moralistic shaming movements in the past (such as those against slavery, whaling, piracy, and punitive torture) have been effective over long stretches of time. I also don’t expect war between developed countries to make a comeback any time soon. But civil wars, terrorist acts, government repression, and genocides in backward parts of the world are simply too capricious to allow predictions. With six billion people in the world, there’s no predicting what some cunning fanatic or narcissistic despot might do.