This is designed into BitCoin and often touted as a feature… every single transaction is recorded. Forever. Not just Silk Road, everyone can see what you’ve ever done if they manage to figure out your wallet number. Which isn’t all that hard, since anonymity is a joke if you make a surprisingly small number of transactions. Only ‘safe’ way is to put some money in a new wallet (not from your main wallet, that transaction will be clear as day - and I hope you’re not putting this cash in from your credit card), do your stuff you don’t want anyone to find out about, and never touch it again. Or you could use it only for the naughty stuff and freaking be careful with never letting your info get tied to it.
You can use a bitcoin tumbler, but then you may end up with stolen coins since the people using them are people who don’t want other people knowing what they’re doing. Like using Tor, it is in and of itself suspicious to law enforcement. And people have been traced through tumblers, they’re not magic.
And now Bitcoin isn’t even convenient to buy anything with, so there went the last reason.
