Previously, I offered a high level definition of public diplomacy. Below is a slightly modified:
Public diplomacy is the direct or indirect engagement of foreign publics in support of national security, political, cultural, and economic objectives.
Ok, so what about the following, more specific definition:
Public diplomacy involves understanding, influencing, developing relationships with and providing information to the general public and civic society abroad, in order to create a favorable environment for achieving national security, political, cultural and economic objectives
To many, the list at the end of both is in many ways redundant (e.g. economic security is essential for national security), but not to everybody. In the latter definition, public diplomacy is an indirect action that shapes the environment. The former includes a broader range of active persuasive techniques.
Either way, public diplomacy is a factor in all facets of international engagement and discourse. Everything we say and everything we do, as well as what we fail to say and do, has an impact in other lands. Spoken nearly sixty years ago by presidential candidate Eisenhower, the meaning is timeless.
It is one thing to have an organizing principle, what is necessary is an organizing principal. Under President-elect Obama, it is clear that we'll have the latter. Get both and Congress will get onboard (and then funding). We have precedent. It's called the Smith-Mundt Act of 1948.
Sixty years ago, Congress also had little confidence in the State Department's ability to communicate overseas. They slashed the budget for international broadcasting in half. The final version the Smith-Mundt Bill that was passed was largely a response to this lack of confidence. Many safeguards were put into the Bill to address the (often appropriate) concerns of Congress, including a prohibition against domestic dissemination of information products produced by State for overseas publics, the most intense "loyalty" checks possible (security clearances), and oversight committees.
The result was a bill that sought to arm the United States in a "war of ideology" in South America, Europe, and elsewhere. After many hearings, amendments, and even a reintroduction (it was known as the Bloom Bill in the 79th Congress), the 80th Congress passed the Smith-Mundt Bill after witnessing first-hand the tempo and volume of enemy propaganda and misinformation that was attacking reconstruction and stabilization programs known as the Marshall Plan.