Modern Maunsell forts as fixed air-defense sites

Would a NATO version of the Maunsell sea forts provide useful offshore defense?

They could support peacetime air surveillance, but a wartime site would be a fixed, known target requiring its own defenses.

The value depends on mission: routine monitoring requires less protection than wartime air defense. A fixed installation cannot disperse or maneuver, so its defensive burden must be included in the concept. A sea fort could host radar for persistent peacetime surveillance of civilian and military airspace. Once war begins, however, its known coordinates make it a target whose missiles, sensors, and crew all require protection.