You've been at the United Nations for nearly four years. What are some things you have not been able to get done that you would have hoped to?
I feel, broadly speaking, very good about what we've accomplished. The one issue that is high profile that is without doubt still very frustrating is the repeated decisions by Russia and China to block any meaningful action in the Security Council on Syria. Those decisions are made at the highest levels in Beijing and Moscow. We've worked at every level to try to change what we think is a self-defeating course of action from their point of view. They seem for the moment determined to protect Assad at all costs, at the expense of the blood of the people of Syria.