Why dry docks become strategic targets

Were enemy floating docks and repair facilities priority targets for naval planners?

Yes. Destroying or disabling docks restricts an opponent's ability to repair warships, so planners repeatedly treated them as high-value targets.

Docks are obvious targets because disabling them can immobilize warships without sinking every hull. German and Italian planners had reason to hunt British floating docks, while plans for attacks such as Pearl Harbor also considered fixed repair facilities. Britain repeatedly bombed, mined, raided, or demolished enemy dock infrastructure in continental Europe. A destroyer packed with explosives could deny a large graving dock to the enemy for far longer than a conventional raid on an individual ship. Repair infrastructure therefore belongs in operational targeting and naval intelligence alongside the warships it supports.