as we know so many reason to make controversial bit coin currency in practical or real media sanitation. if  we observe very carefully  few past few years we have seen that  criminal activities  or occurrence  are occurred by the help of hackers and trader make it famous moving thousand of dollars outside by cheating  with government law enforcement for that reason value of bitcoin increasing very high. even they make money away from center bank and government unable to hold money from general people and through this process people convert this money into different things. i think this is enough for making controversial and what do you think about my think ?