It is well known that black tea is the most popular drink in the UK. A scientist in the US sparked the debate by publishing her research that addition of a bit of salt improve the taste of black tea. It is a dispute between the US and UK since Tea Party Incident in which boxes of tea were dumped into sea. For British people black tea is a symbol of their identiy. They felt as if their pride was hurt. The US embassy in London said it was not the state policy and distanced itself from the dispute.
Black tea originally grown in China was transplanted to India where the climate was good for black tea. Later it became popular in the UK. The manuscript written in China in 8th century already mentioned the addition of a bit of salt improves the taste of black tea. The American scientist found that sodium ion in salt react with bitter component in black tea.
Many Britons countered this opinion by saying the addition of salt never improved the taste. There is a person in another country who says that black tea made from tea bag common in the UK is not authentic.