Fuses should be rated to protect the wiring so choose the fuse according to the gauge of wire used. The design intent is that under short circuit conditions the fuse will blow before the wiring is damaged.
I'll never forget the scene in a college carpark. My mate had "repaired" a fuse on his 60's Triumph Bonneville which kept blowing by wrapping it in silver paper from a cigarette packet. When the intermittent short circuit that had been blowing his fuse occurred again the wiring glowed red hot and the insulation went up in smoke as he rushed to disconnect the battery. Seems funny now but was seriously scary at the time.
