The central purpose of international humanitarian law (IHL) is to alleviate the suffering caused by war to the greatest extent possible. To do this, IHL requires states to ensure the protection of civilian populations and, regulates the means of warfare, including prohibiting the use of certain weapons. The International Court of Justice (ICJ) describes IHL’s regulation of weapons as “intransgressible principles of international law,” to be observed by all States. Yet, women do not enjoy the equal protection of these intransgressible laws on weapons. The major weapon used against women and girls in today’s armed conflicts is rape. However, rape is not categorized by states as a “real” weapon, one that must be evaluated under the “intransgressible” principles of the laws of weaponry. Thus, unlike other weapons unlawful to use in armed conflict, such as starvation, herbicides, and chemical weapons, rape has never been declared to be an illegal weapon or means of warfare. Consequently, rape victims, who are disproportionately women, are denied the full panoply of remedies for their injuries, including sanctions on the violator state, available to other victims of unlawful weapons. Further, the failure to classify rape as an illegal weapon of warfare is a dangerous lapse in global security. The failure to classify rape as a weapon is an affirmative act by states that constitutes a serious violation of IHL.