What mistakes did Lin Zexu make in handling the Opium War?

1. The internal affairs turned into international issues: Lin Zexu blocked the British business community after arriving in Guangzhou, cutting off internal and external contacts and various supplies. In this way, British businessmen were forced to hand over opium. However, this practice turned the anti-smoking movement in China into a diplomatic conflict between China and Britain, which eventually led to the Opium War.

2. Extremely conceited and despising foreigners: Before the war, Lin Zexu was warned by the American consul. And asked Lin Zexu to allow American merchant ships to enter the port to unload goods to avoid losses. However, Lin Zexu didn't agree at all, which led to the insufficient pre-war preparation of the Qing army and finally suffered a big loss.

3. Inadequate preparation for war: Lin Zexu said the famous joke of Qing Dynasty, "Foreigners' legs are straight, so they can't bend". Although Lin Zexu was regarded as the first group of people in China who opened his eyes to the world, his vision was still very limited. Although he was seriously preparing for the war near Guangzhou, the defense lines he built could not defend against the British attack from the rear, which was a great failure.