Operation Urban Warrior was a United States Marine Corps program created as an exercise meant to plan and test Military Operations on Urbanized Terrain (MOUT) and urban warfare in general. It was developed in the mid 1990s by the Marine Corps Warfighting Laboratory partly in response to growing problem on inner-city fighting, and especially made urgent following the Battle of Mogadishu in 1993.
Press materials from the Warfighting Lab in 1997 stated, "..the world is becoming increasingly urbanized and increasingly dangerous" and described a new fight zone called the "urban littoral," or coastal zone where most of the world's population will reside. "Parts of the urban littoral will contain all the classic ingredients for conflict. There will be social, cultural, religious and tribal strife between different groups. Many areas will have scarce resources, including the most basic ones like food and shelter as populations grow and resources shrink even further. The chances for conflict will naturally grow with it".
Some preferred to call it the "Three Block War". The concern that Marines would be made responsible for humanitarian assistance, as evidenced by the Bosnian War, was part of the original planning of the program. According to a 1997 Defense Monitor brief, the Marines were facing the burden of excessive operational tempo related to humanitarian concerns. The importance of getting the military out of humanitarian relief was expressed in the 1997 Center for Defense Information brief.
The program has been called one of the most important in the United States Armed Forces. This is because, even though the U.S. is believed to have one of the most powerful conventional military forces in the world, many of the more powerful weapons systems intended for use fighting in open places are useless in urban settings. This was the case in some forested regions of Europe, and in open deserts encountered during the Gulf War and Iraq War. Lines of approach through cities tend to be long and narrow, with sharp turns, civilians, street traffic and local commerce. This environment is one where heavy fighting vehicles like the M1 Abrams can not maneuver well, avoid being seen from a long distance by potential hostiles, nor be certain that all ground surfaces will support vehicle weight.