I think it is just a every time returning correction based on FUD. The fundamentals are still great and I expect China will crack down on things only temporarily as in the past. Bitcoin and cryptocurrency is a huge opportunity for China and they will recognize this.
It shouldn't surprise me if the bottom is found here or around 3500 and we go to a new all time high again. Except for China the fundamentals are still great, think of the Jappanese and Russians involved in mining, the growing adoption on wall street and the upcoming side chains and other second layers. HODL!