Doctrine. A doctrine is a body of principles, beliefs, statements of policy, and teachings. From a military standpoint, a doctrine defines what a Service is all about, from its structures, war-fighting principles, and the way it conducts business.
Strategy. Strategy refers to the overarching plan or approach that is developed to achieve a particular objective. It involves making decisions about how resources will be allocated, which objectives will be pursued, and what overall approach will be taken. Strategy is typically developed at the highest levels of command and is focused on achieving long-term goals.
Tactics. Tactics, on the other hand, are the specific actions that are taken to execute a strategy. Tactics involve the detailed planning and execution of specific operations or manoeuvres, such as the movement of troops, the use of weapons systems, or the deployment of specialized units. Tactics are typically developed by commanders at the operational or tactical level and are focused on achieving short-term goals.
Strategy vis-à-vis Tactics. In military operations, strategy and tactics are interdependent and must be carefully coordinated to achieve success. A good strategy must take into account the tactical realities on the ground, while effective tactics must be consistent with the overall strategic objectives. Effective coordination between strategic and tactical levels of command is essential for achieving success in military operations.