* funding terrorist,
* money laundering,
*kidnap for ransom using bitcoin, and etc,
this has been the issue eversince but like what answered from the past, even without bitcoin still those illegal doings will exist.
they will do everything using their knowledge and ability to hide their activities.
bitcoin just become controversial because of the popularity and so many users but the thing is no matter what they called bitcoin still the reality speaking that this is also helpful in economy .
Its like a double edge sword, you can use it in both directions. All such fraudulent activities are happening for centuries. Even today most of such fraudulent activities are done in digitally using USD. You can use BTC to transfer funds to your client instantly in country where he is denied banking facility or other way around, choice is yours. We need to understand that BTC is not only about money laundering, ransomware etc its a financial system in which everyone can join without any filtration.