The pilot reported that upon runway contact, the airplane began to pull to the right and not slowing down like it normally would. The pilot attempted to keep the aircraft on the runway centerline by applying full left rudder. Subsequently, the pilot lost directional control as the airplane spun perpendicular to the runway. The nose landing gear collapsed, and the airplane came to rest on the runway. The pilot reported that he was not sure if the green gear down indicator lights were illuminated prior to landing. The airplane sustained substantial damage to the lower skins, stringers, and box beams on the fuselage. After the airplane was recovered from the runway, the pilot noticed the landing gear circuit breaker was tripped. Upon resetting the circuit breaker, the landing gear lowered and locked in the down position. Postaccident examination did not reveal why the circuit breaker had tripped.