Answer:
Due to non-seriousness.
Step-by-step explanation:
United states of America took so long time to grant women suffrage because the women were not serious of getting their rights. Men in the American society can't provide equality to the women because they considered female inferior and think themselves superior in the society. This concept of men in the society prevent giving equality and rights to the women so no realization is the main thing which is responsible for the long time to grant women suffrage.