We all recognize that climate change is a supremely important issue of our time, which requires both trans-national and trans-generational collaboration and shared responsibility. What we haven't yet fully appreciated, argues political philosopher Henry Shue, are the ethical considerations surrounding the fact that the next one or two decades will determine whether climate change, which already has led us to dangerous effects, will surge into inescapably disastrous effects.

The people alive today thus represent a pivotal generation in human history. For the past two centuries humans have undermined our climate at an increasing rate, in ways that the present generations are the first to fully understand, and the last to be able to reverse. But our responsibility for decisive and immediate action rests on three special features of the relation of our present to the future, that many have failed to realize (1) future generations face dangers greater than ours even if we act robustly, (2) the worsening dangers for future generations are currently without limit, and (3) a less robust effort by us is likely to allow climate change to pass critical tipping points for severely worse and potentially unavoidable future dangers.

Shue, a renowned scholar of ethics, politics and international relations who has been studying the ethics of climate change for the last two decades, guides us through what our ethical responsibilities to others are, both across the world but especially over time, and what those commitments require us to do in addressing the climate change crisis, now and forcefully.