There has been considerable discussion within the national security community, including a recent workshop sponsored by the U.S. State Department, about the use of social media for extracting patterns of collective behavior and influencing public perception in areas relevant to arms control and nonproliferation. This paper seeks to explore if, and how, social media can be used to supplement nonproliferation and arms control inspection and monitoring activities on states and sites of greatest proliferation relevance. In this paper, we set the stage for how social media can be applied in this problem space and describe some of the foreseen challenges, including data validation, sources and attributes, verification, and security. Using information analytics and data visualization capabilities available at Pacific Northwest National Laboratory (PNNL), we provide graphical examples of some social media "signatures" of potential relevance for nonproliferation and arms control purposes. We conclude by describing a proposed case study and offering recommendations both for further research and next steps by the policy community.