The United Nations session in New York was unable to agree what "terrorism" means. At issue is the status especially of Palestinian terrorists - whom some Middle Eastern countries still cast in the role of "freedom fighters". The daily murders of children and other non-combatants thus become mere statistics-of-war in the Palestinian struggle.
The UN has a role to play as a forum of nations, but if it cannot come to terms about a primary item like terrorism, one is allowed to wonder what that role could be. One suspects the UN itself to be quite incapable of defining its own role so as to satisfy everyone.
When one looks at the UN website one isn't surprised to see much worthiness and fudgy handwringing. This, for example from the UN's environmental committee, UNEP:
"UNEP inspires, informs and enables Nations and Peoples, Children, Youth and Business to improve the quality of life without compromising that of future generations."
But people who formulate a statement of that sort are ill-suited to the task of producing an agreeable definition of "terrorism". In attempting to combine worthy handwringing with realpolitik, the UN can succeed at neither role.