As I understand it, the B1 was originally designed as a nuclear bomber, but has been used through modifications as a non-nuc bomber in the conventional wars we have been fighting.
The B-1B was designed and fielded as a nuclear delivery system. Around 1991/92 the AF started to experiment with conventional weapons loads and subsequently the B-1B was decertified for use with nuclear weapons and relegated to only conventional weapons use.
i thought it got it’s nuts cut due to the arms treaties
Armament
Hardpoints: 6 external hardpoints for 50,000 pounds (23,000 kg) of ordnance (use for weapons restricted by arms treaties[105][193]) and 3 internal bomb bays for 75,000 pounds (34,000 kg) of ordnance.[194]