Final answer:
In a BCT, tactical sustainment is provided by various support units responsible for logistics, transportation, and supply functions. Strategic planning includes stockpiling critical materials for wartime as practiced by the U.S. Defense National Stockpile Center. Engineers also play a vital role in maintaining operational capabilities.
Step-by-step explanation:
The element that provides tactical sustainment in a Brigade Combat Team (BCT) is typically composed of various support units that are responsible for maintaining the brigade's operational capabilities. This includes logistics, transportation, and supply functions that ensure the BCT continues to operate effectively during a mission. The discussion around tactical sustainment is not just about immediate needs but also involves strategic planning for wartime scenarios. Governments need to ensure that they have the required resources, which may involve building stockpiles of critical materials in case supply lines are disrupted during conflict, as is the practice of the U.S. Defense National Stockpile Center. Furthermore, engineer units play a crucial role, as illustrated by the 1995-1996 peacekeeping mission in Bosnia, where engineers were key in establishing infrastructure like pontoon bridges to facilitate supply and troop movements.