[tinfoil hat]
I'm a sucker for a good conspiracy. Some are just amazing and really a good read. Some though, like Smedley Butler, are shocking in their truth. Take July 23rd, 2012, a coronal mass ejection shot out of the sun. The blast of x-rays and solar radiation missed the earth by 9 days. It was roughly the size of the "carrington event", which actually did hit the planet.
What happens when it hits, is basically a planet wide EMP. Back in 1859, it just arced electricity along the telegraph lines and set fire to some paper. Today though, it would fry our electrical infrastructure to a degree that it would take us 4 to 10 years to rebuild (according to a paper written with the help of NASA and the university of Colorado). It's all about the way we distribute power across the nation via high voltage lines. First world countries would become third world countries overnight.
The implications of this are shocking. I've been through a 5 day blackout. It was chaos, panic, and desperation all rolled into one. It doesn't seem like much on the surface, but the reality was different. There was no gas for cars. There was no light at night. There was no heat in homes. There was no food in the stores. It was less than a week, but it got bad really quick. The idea of 4+ years without electricity scares the shit out of me.
Just like it should. How many people know how to start a fire? How many people know how to hunt or fish? How many people know what plants are edible? How bad would it get when people actually feel real hunger for the first time. I'm not talking about "ooh, I'm on a diet and hungry all the time" kind of hungry. I'm talking about literally not eating for a couple days and having no idea where they will find their next meal. Very few people in a first world country can even comprehend that feeling.
So long story short, I see things that threaten our way of life (as you mentioned emp, disease, etc.). They are very real threats and could happen tomorrow. Then I see things like this "oregon crisis" and wonder what would happen to humanity if something, anything were to happen.
[/tinfoil hat]
Citations:
Smedley Butler
Carrington Event
2012 Coronal Mass Ejection
Report on CME repercussions
TLDR: Yep, those are citations(ish). Shit can happen, really, unbelievably bad shit. If people can't figure out pumping gas, I fear for the future of humanity.