According to Lin, the main motivation for the British trade is to make money of the Chinese people. His argument is that this was Britain's goal, even though the biggest resource they were trading (opium) was a highly addictive and dangerous drug. Lin also points out how it is contradictory that this substance is banned in Britain yet they can still trade/bring it to China.
This opium trade causes extreme tension between Britain and China, as millions of Chinese citizens became addicted to the drug. Despite Lin's threat to cause war if the British continued to bring in opium, the British continued to sell it to Chinese citizens. This eventual leads to the Opium Wars (1839-1842).