We all know that Bitcoin is also popular to criminals because they can use it without exposing their identity. It will be more convenient to them to use Bitcoin so that they can hide their identity. Do you think that terrorist groups like ISIS use it for their transactions?
I think now ISiS or any terorrist in this world with a knowledge in crypto is already use to for payment on any crime transaction like for buying guns or any deadly weapons on black market in deep or darkweb that provides an secret plan that no one knows can see this thing.