In May,1999, China's embassy's was bombed in the Republic of Yugoslavia by American army. This event irritated the “angry youth” and they made remonstration to it. Chinese hackers attacked many American websites. In the demonstrations, the most eye-catching slogans calling for a boycott included ‘Burn all McDonald’s in China’ and ‘Damage American intellectual property by practical action: free provision of pirated software’. After the Hainan Island incident in April 2001, hackers in both countries began their fight again. Most of the “angry youth” believe that the United States doesn’t want China to develop.