Submarines primarily operate under which condition?

Submarines are designed to primarily operate underwater, allowing them to conduct a variety of missions undetected. This capability is crucial for strategic military operations, such as surveillance, stealth attacks, and intelligence gathering. Operating underwater provides submarines with the advantage of avoiding radar detection and surface threats, allowing them to remain concealed and safer from enemy actions.

While they can surface as needed for various operations, including communication and replenishment, the core functionality of submarines revolves around their ability to operate submerged. This operational advantage is fundamental to the role and effectiveness of submarines within naval warfare.