If buying heroin means you are supporting the Taliban, then eating meat means you are supporting animal cruelty and abuse for the countless deaths in the slaughterhouses by the seconds; countless poultry bred, stuffed fed and infused with hormones to be slaughtered the next moment.
And if you donate money (or buy) to a privacy program development such as Tails, PGP, Tor or encryption, you are supporting terrorism by improving the technology for anonymous-privacy communication and network, isn't it?
Then does supporting and advocating bitcoins means you are supporting criminals or terrorists as well since it's an uncontrolled currency that they might use?
Paying U.S. taxes supports the terrorists too.