 Complete the following phrase:  Informal empire, like many imperial relationships, is difficult to classify and reduce to a prescriptive definition. In the instance of the British informal empire, the character of the relationship varied widely. The Chinese intensely opposed any foreign control over China or its economy, and both the First and Second Opium Wars were fought between China and several Western powers, resulting in Chinese defeat and the increase of both formal and informal foreign power. South American governments were often willing partners in the extension of British commercial influence, but military action was sometimes taken against those who tried to apply protectionist policies see for example, the 