First and foremost, public diplomacy is the term used to describe states behaviour by influencing foreign countries, through media or speeches, their national self interest.
A good example is Obama’s recent visit to India. Not only has he talked positive about India’s progress on the development of their economy he also has welcomed the idea of India’s permanent seat in the Security Council. It does not necessarily mean that they will have a seat but when we take the fact that India has a seat for the next to years in the security counsel into context, it could be argued that President Obama is promoting national interest by praising India. Furthermore, the trip was important for future economic relations as Obama said:

“It is my firm belief that the relationship between the United States and India --- bound by our shared interests and our shared values will be one of the defining partnerships of the 21st century. This is the partnership I've come here to build. This is the vision that our nations can realize together.”
(http://www.bbc.co.uk/news/world-south-asia-11711007)
However, the Republican Senator Ed Royce wrote President Barack Obama:
“As you know, six foreign companies are competing to sell India 126 new multi-role combat aircraft in a deal that could be worth as much as $11 billion. India's selection process for this aircraft is advancing, with two US companies under active consideration,"
Quote (http://news.rediff.com/slide-show/2010/nov/02/slide-show-1-obama-visit-lets-move-india-away-from-russian-weapons.htm)
Therefore, it can be argued that Obama’s visit and the positive promotion of India is some sort of public diplomacy as it builds up the economic relation and helps to boost America’s economy.
India has a long history of Human rights abuses such as unlawful killings, torture, unjust treatment of women, discrimination against other tribes, corrupted use of police force and many more. Nevertheless, Obama has not raised the human rights issue on his trip which led us to understand the importants of public diplomacy. A realist would argue that states on foreign policy do not priorities human rights agenda but solely self interest.
However, according to the BBC website president Obama’s India trip will be followed by visits to Indonesia, South Korea and Japan on a 10-day Asian which was aimed to tighten economic relation and boost US exports.


Read more: http://www.dailymail.co.uk/news/worldnews/article-1325075/Obama-India-visit-Biggest-US-President-40-planes-6-armoured-cars.html#ixzz14ubxNJJ6