Argument I keep hearing are "terrorist use it" "money laundering" - if that's the case ,terrorists also used airplane, let's ban air travel - they also use cash ,let's ban cash altogether (yes, there is a war on cash) , they use guns , let's ban guns. However, gun industry (defense sector) and airlines have massive pockets.
This is the best argument that we can use against people who think that they know much better than Satoshi when it comes to Bitcoin. The idea that since some evil people are using Bitcoin then we should be limiting or banning the use of Bitcoin is one of the most foolish idea ever. It is not the fault of Bitcoin if there would be people to use for their own evil interest. Singling out Bitcoin of all the currencies used for frauds is not doing justice and is very unfair to say the least.
It is just sad that these people using those illogical arguments are actually also representing the selfish interests of their own industries (maybe they want to protect what they are representing here) that is why we have to be careful not to caught the same virus they have in their mindset.
Soon these people will realize that Bitcoin is unstoppable and is here to stay for good...they might even join the Bitcoin bandwagon silently and enjoy the profits they can get out of it.