In a world beset by many grave problems that threaten to unleash a perfect storm at short notice, many people bemoan the dearth of responsible and high-quality leadership to point the way forward to a more prosperous, peaceful and just future.
Yesterday's leaders may no longer be in power but have much to contribute by drawing on their accumulated experience, wisdom and detachment from the everyday concerns of making and executing public and foreign policy.
The two great existential challenges of our time are climate change and nuclear weapons. With regard to the latter, between them, Russia and the United States hold 90 to 95 percent of the world's stockpile of nuclear weapons.