After more than a year of contentious negotiations, diplomats from 109 countries meeting in Dublin agreed Wednesday on a treaty that would outlaw the use, production, transfer, and stockpiling of cluster munitions, which have killed and injured thousands of civilians over the last four decades... Six of the world’s leading users and producers — Russia, China, the United States, Israel, India and Pakistan — did not attend the conference, and have said they would not sign any ban.