Before the Opium War gunboat only increase with cheap goods destroyed in the Great Wall of China to close the door, so that China become an independent run for many of the semi-colonial imperialism.

• 只有鸦片战争才用炮舰加廉价的商品摧垮了中国闭关自守的万里长城，使独立自主的中国变成许多帝国主义角逐的半殖民地。