Why didn't anyone on the outside step in to try and stop the holocaust?

They didn't understand. You have to take into account that most people back then thought that it was some media stint. The holocaust at that time was too big (in my opinion) for some people to wrap their mind around.

Well from the way I see it, if other countries were to get in on the holocaust it would just make it worse becuase then Germany would have to start a war with those countries and it would be a big mess and I'm sure other countries feared that something like that would possibly happen which is why they didn't act upon it and if they did they would be causing problems for their own country which is what they didn't need.