Conspiracy theories attract those who are trying to make sense of the world.
For Muslims observing events like 9/11 or 7/7, and more recently the rise of Islamic State, it is often easier to find comfort in such explanations than to accept any roots to these developments may exist in their own faith. It can't be us, so it must be Israel, India, the US or any combination thereof.
Similarly, consider those unable to accept that the UK, and perhaps even their city or town, voted to leave the European Union. Any explanation rooted in skullduggery or deception has a basic appeal. It can't be happening because people wanted it to, but because of ........... Putin, the manipulation of Facebook, because of 'dark money' or even an alliance between the Conservative Party and Moscow.
It is fascinating how it was once the right who believed in KGB manipulation and 'reds under the beds'. Today you are more likely to find a Guardian or Times columnist worrying about Russian influence in Britain, than a loyal subscriber to the Daily Mail.
It is not that conspiracy theories are always troubling. Often they are silly. But they attract the troubled, unhappy and the lost. And at the moment it is the political centre, and that part of the left that was unseated by Corbynism, that has nowhere to turn to. Except to conspiracy theories.