today it's China, but tomorrow another big country could do the same. Who knows really? Nobody can be sure this will not happen. So the future is really uncertain.

Truth is bitcoin has grown into a bubble last weeks, and now the bubble is blasting. I wouldn't be surprised if it went down to 200/300 dollars and stayed there for a few month or even years. Just  like the Internet companies in the early 2000's. What can you buy with bitcoins? Drugs, and maybe a gun, that's about it.