Public diplomacy work entails numerous partnerships with interagencies, NGOs, and more broadly civic society. These partnerships are necessary for a number a reasons. First, a government does not have the capacity to carry out all of its envisioned PD initiatives. PD officials, especially in the US State Department, are already understaffed and spread thin with the projects they are assigned. Second, many initiatives would not be as approachable to locals coming directly from government officials. It is more comfortable for a public to interact with foreign peer groups. And lastly I’ll mention that it seems more realistic that a separate entity would be more effectively evaluate and commit to a long term engagement than the government with rapidly changing interests depending on current world events. A government has to focus on whatever is most crucial at a given time. Therefore nongovernmental organizations can carry on the work that is necessary to maintain strong diplomatic ties with nations less on the radar of the US government at any given time.
Using the term engagement to describe diplomatic efforts can make the work a bit more ambiguous. However, I think it is a more accurate term when it comes to separating the type of interactions had by governmental officials versus nongovernmental individuals or organizations abroad. Engagement in the context of public diplomacy is descriptive of the interactions nongovernmental persons and organizations have with foreign publics that can be or not be on behalf of government initiatives.
This term is salient particularly when considering cultural activities and exchanges related to public diplomacy. For instance, if a dance company was sent abroad to lead educational workshops and perform for the public, I would think of this as cultural engagement under the umbrella of public diplomacy. Although these engagements add to the overall efforts to inform a foreign public about US policy, it is mostly about building international peer relationships.