CIMSEC – The Marine Corps is faced with an intensified challenge of contested logistics as it employs its novel concept of Expeditionary Advanced Base Operations (EABO). EABO calls for Marines to act as Stand-in Forces using low profile, highly mobile Expeditionary Advance Bases (EAB) that will likely be within an enemy’s Weapons Engagement Zone (WEZ). Supplying these bases will be difficult since their location is expected to frequently shift, and reliance on the conventional global logistics chain may not be responsive in a contested environment. A possible solution is the use of unmanned or autonomous Self Propelled Semi-Submersibles (SPSS) to provide logistics support. It is important to consider how SPSS will be classified under domestic and international law, and what rights and obligations will be imposed on them during peacetime and armed conflict.