Due to its unsuitability for bombs, the militaries of the world (in the '50s) didn't invest into researching Thorium. Industrial inertia (and sunk costs) and Uranium being good enough lead us to where we are today.
It is 'technically' possible to make a U-233 bomb but the effort required is so far above U-235 bombs that for any nation able to do the former, it's much easier and cheaper to do the latter.
U232 makes a very heavy gamma ray that makes it difficult to work with the resulting U233, that is, you get killed trying to make a bomb from it. Also the fabrication of solid U233 is difficult because of the U232 contamination.
If Thorium is used in an LWR the neutron exposure on the Pa233 is enough that the U233 produced is hard to work with. If you had a special reactor like the ones they use to make weapons grade plutonium you could make weapons grade U233.
As for the various liquid salt reactors, it all depends on whether or not and how effectively Pa is removed. The Pa + neutron reaction hurts the breeding ration by consuming both Pa and neutrons. To maximize the breeding ratio it would be desirable to separate out the Pa and put it somewhere away from neutrons where it can decay to U233. If you had a process for this that was incredibly efficient than you could make weapons grade U233.