One of the main jobs of a fuse is to protect the wire.
From
https://www.bluesea.com
https://www.bluesea.com/support/arti...uit_Protection
Electrical shorts are the number one cause of fires on boats. In fact, more than half of boat fires are electrical in origin. More than half of those are caused by short circuits, most in the DC circuits. If you add any circuits to your boat, make sure they are protected.
Important factors to consider when adding circuit protection to your boat’s DC electrical system include:
Ampere Interrupt Capacity (AIC)
Mounting location
Overcurrent protection (7/40/72 Rule)
Ignition protection
If more current flows in a wire than the wire is rated to handle, the wire can heat up, its protective insulation can melt, and the heated wire can start a fire. This overcurrent condition can occur, for example, when a short circuit occurs. Fuses and circuit breakers are used to limit the amount of current that flows through circuit wires. Except for those wires that are intended to carry starting currents, every positive wire in the DC main power distribution system must be protected by a fuse or circuit breaker.