To get the economy back on track, China is trying to champion its domestic companies and reassure entrepreneurs that it¡¯s ready for business.

Its efforts are running into a problem: an online army of Chinese nationalists who have taken it upon themselves to punish perceived insults to the country ¡ª including from some of China¡¯s leading business figures.

In recent weeks, bloggers who usually rail against the United States have turned on China¡¯s richest man, calling him unpatriotic, and encouraged boycotts that have wiped out billions from his beverage company¡¯s market value. When fellow tycoons defended him, they were attacked as well, by users whose profiles featured photos of the Chinese flag.