Domestic violence is the most common form of violence against women internationally. In studying child protection around the world, UNICEF collected data from 1999-2006 regarding whether women in 67 countries (not including the US) felt that domestic violence was ever acceptable. On average, half of girls and women aged 15–49 responded that a husband or partner is justified in beating his wife under certain circumstances.
Somehow we're not surprised. Women are raised in the same cultures as men, and if men feel justified in using violence against their partners, is it really a stretch for women to also believe that men are justified in using violence? Though the US wasn't included in this survey, things don't look much different here.
You can view data by country here.