Context: Nations export culture, ideology, and people to create soft power. They export because they have a competitive edge, superior education system, rich culture, superior political system, and military might.
What are the benefits of Soft power?

1. Competitive edge for the “exporter” nation: Since people retain cultural ties and residual loyalties to the land of origin, 
2. Create a feedback loop and reinforce hard power: For example, South Korean movies, music, games and dress codes are influencing millennials everywhere.

About India and its soft power in ancient times

• India has soft power in Southeast Asia and the Far East. Buddhist missionaries won hearts and minds. Naval conquests established Indophile cultures in Indonesia and Cambodia.

About the soft power of the UK during Colonial times
The soft power of the UK was accumulated during the time when the sun never set on the British Empire. That soft power still has its impacts. For instance, 

• The EU’s business language is English (though the UK is no longer a member), 
• Pop music everywhere has English lyrics, 
• English is America’s official language and is widely spoken in many countries like India.

Does soft power always benefit exporter nations?

• No, if the soft power is being exported for the wrong reasons, then the soft power exported can rebound horribly wrong on the exporter. 
• The lessons of Germany, Italy and Japan in the 1930s is a classic example.

How did the soft power of Germany, Japan and Italy lead to the demise of their own?

• In the 1930s, Japan started dreaming of a “Greater East Asia Co-Prosperity Sphere” created by annexing chunks of mainland Asia. 
• Similarly, Germany’s Third Reich started fantasising about a Greater Germany (Gross Deutschland) and the enslavement and extermination of inferior races.
• For achieving that purpose, Jews, Gypsies, Catholics, etc., were herded into extermination camps in Germany. Citizens left Japan in search of greater political stability. The Italians left as Mussolini tried to grab chunks of Africa, and spoke about a New Roman Empire through the “Right of Blood“. This resulted in
• Emigrant scientists and engineers (including Italians like Enrico Fermi, non-Jewish Germans, and many Jews) invented nuclear weapons and gathered information about the Axis war efforts.
• General Dwight David Eisenhower, who oversaw the Allied invasion of Europe was born into a German immigrant family.
• The US Army’s 442nd Infantry Regiment, which won more gallantry awards than any other US formation, was entirely composed of volunteers of Japanese descent.
• The advocates of Gross Deutschland and the Greater East Asia thing mostly ended up dead, after killing millions of their own countrymen. So, Soft power can rebound horribly to the exporter, if exported for the wrong reasons.