Many, many moons ago I participated in a evaluation task for a DARPA-sponsored project involving speech recognition, machine translation and information extraction. I worked answering questions such as
DESCRIBE THE RELATIONSHIP BETWEEN [ Dow Jones 2020 ] AND [ Bolivian coup 2019 ].
My work on the topic sadly never got published but you can see other existing papers on the topic.
A possible system for this will search for entities related to one topic, the find entities related to the second topic and look at the intersection. If the intersection is empty, it'll expand on some entities until a link is made (for example, a possible relationship for the example query above might be Tesla Motors given its founder famous Twitter quip).
It would be nice to see a system solving such queries deployed against the excellent Reddit API. It might get people talking across multiple subreddits and enhance thinking outside the box.