LWR technology is limited by steam’s low heat transfer capacity, and the pressure needed to keep very hot water a liquid.
LFTRs have no water in the reactor. Liquid fluoride salt (without any radioactive materials) transfers heat out of the reactor. The salt remains liquid at temperatures much higher than the reactor, at atmospheric pressure.
(At Fukushima, the reactors were shut down properly before the tsunami struck. Fukushima reactor core damage, hydrogen buildup, and radiation leakage was from loss of water coolant.)
LFTRs can be installed even in deserts. LFTRs can be located in small sites wherever needed, or transported for military or disaster relief use.
Use reactor heat for generating electricity and industrial processes. Transfer unused heat to air or water.
If water got in the reactor (e.g. a tsunami or hurricane), it would simply boil away. Nothing in a LFTR reacts with water or dissolves in water, and all transuranic elements are strongly chemically bound to the fluoride salts. If there was structural damage, passive safety systems would simply dump the fuel into passive cooling tanks. (Later re-heat and pump fuel back into the reactor.)