All of the great leaders have had one characteristic in common: it was the willingness to confront unequivocally the major anxiety of their people in their time. This, and not much else, is the essence of leadership.
There will always be disputes between nations which, at times, will inflame the public and threaten conflicts, but the main thing is to educate the people of the world to be ever mindful that there are better means of settling such disputes than by war.
And if we must educate our poets and artists in science, we must educate our masters, labour and capital, in art.