The changing of the guard on the 38th floor of the U.N. building, with Antonio Guterres taking over for Ban Ki-moon as U.N. secretary-general, came as notions about peace and conflict are undergoing a subtle change. In particular, the role of resources — and especially water — is getting the recognition it deserves.

This has been a long time coming. Both Ban and his predecessor, Kofi Annan, argued for some two decades that protecting and sharing natural resources, particularly water, is critical to peace and security. But it was not until last November that the issue gained widespread acknowledgement, with Senegal — that month's U.N. Security Council president — holding the U.N.'s first-ever official debate on water, peace and security.

Open to all U.N. member states, the debate brought together representatives of 69 governments, which together called for water to be transformed from a potential source of crisis into an instrument of peace and cooperation. A few weeks later, Guterres appointed Amina Mohammed, a former Nigerian environment minister, as his deputy secretary-general.