1. Who invented this technology?
2. Can we control it?
3. What is the danger?
At this stage nobody knows who the inventor of this technology is.... Satoshi is just a name... and it might even be a government organization. These countries cannot control it, and most governemnt use the local currency {fiat} to control their citizens. Some countries need full control to manage and prevent possible financial collapse.
The dangers are the unknown.... or the lack of control.
The government definitely cann't control it, just like nobody else can. I think that is one of the main issue that they have with it. Just as they want to control everything else, they want to control Bitcoin too which isn't possible. Obviously one could use the blockchain and run analysis, but that would take up way too many resources on a wider scale.
It's risky just as any other investment is. It might be more stable in the future.