Some possible synonyms for the phrase "are hostile to" include "are antagonistic towards," "are unfriendly towards," "are opposed to," "are against," "are combative towards," "are resistant to," "are critical of," "are disapproving of," "are disdainful of," and "are unsympathetic towards." These terms all suggest some degree of animosity, negativity, or resistance towards a person, group, idea, or object. Depending on the context, they may imply different levels or sources of hostility, such as ideological differences, personal conflicts, cultural biases, or emotional reactions. It's important to choose the right synonym for the intended tone and meaning of the sentence.