Ideological infiltration

After the Google announcement, searches on its google.cn search engine turned up images and sites previously blocked, including pictures from the 1989 crackdown on pro-democracy protests in Beijing. Other searches remained restricted, carrying messages warning users that some content was blocked.
China's ruling Communist Party, wary of the Internet becoming an uncontrolled forum for the country's 360 million Internet users, is unlikely to allow Google to avoid repercussions.

"Hostile Western forces have never abandoned their strategic schemes to Westernise and divide us, and they are stepping up ideological and cultural infiltration," the Party's chief propaganda official, Li Changchun, wrote last month.

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From a dictionary, "ideological" means "based on or relating to a particular set of ideas or beliefs" but I wonder what it means here.