I read the text of the law (it's very short, it seems!) but I'm still not sure where Lightning ⚡ fits into this

If A pays C by Lightning, routing through channels involving B, then it could be argued that B transferred the money from A to C

Of course, Lightning was designed to make it impossible for B to steal the money; B can take the money from A if and only if they first pay C. My fear is that regulators might still abuse this

I guess I should do some research; I'm sure someone has thought of this already 😜