J. Bryan Hehir of the Harvard Divinity School argues that the legal norm against intervention in other nations' affairs is eroded once it becomes impossible to ignore the moral imperatives to rescue those in need and/or end violations of human rights. That said, he favors a prudent approach toward intervention, with non-intervention remaining the norm.
NOTE: This lecture was also published in Ethics & International Affairs, Vol. 9 (1995). Read the full article here.