bitcoin is a double edged sword on one hand using it provides security on the internet since no one can trace you down and on the other hand it provides a big opportunity for hackers and black market dealers that use it for selling drugs and other illegal stuff since it provides anonymity,but it all depends on the person that is using it
The bitcoin is not totally anonymous. It is pseudo anonymous. So you can be traced by using the bitcoin.
yes, I agree with you. Some expressed bitcoin is anonymous. But the fact is if you are using bitcoin for illegal things, the authorities still can figure out your position. As is the case ever before.
Bitcoin is open, so yes, if you withdraw coins from an exchange you have verified yourself at, your details will be attached to these coins. The exchange from there can follow all your transactions.
That's why it is important to mix your coins before using them for a specific purpose. It will allow you to get rid of the coins where your details are attached to, and make use of fresh coins.
But I am quite sure that people looking to use Bitcoin for illegal activities are already doing so. If not, then they are very dumb as they rely on the semi anonymity of Bitcoin.