Gold, which was easier to track down and confiscate "back" was historically confiscated in much larger quantities by much tougher guys. This "insured" government debt-backed money that you have today is a result of having heavy money that is ultimately owned by someone who is bigger than you.
While Bitcoin is stolen from some exchanges from time to time, it's much more diffused and it's enormously harder to take bitcoins massively from population than gold.
See also: http://en.wikipedia.org/wiki/Executive_Order_6102
By the way, these "insured" USDs that you have in your account are not owned by you. Try to cash out everything in paper. Or move anywhere at once without asking for permission. Or what would you do when they impose capital controls like in Cyprus or Argentina? Or when your % of total USDs in the economy is going down while Fed is printing more dollars? Or when some new taxation is applied retroactively? Or when some bureaucrat didn't see your tax return papers in time and your entire account is frozen during investigation?
Bitcoin reduces systemic risk like the one present in banking system and shifts the burden on individual users. You can still create a bank if you want, but that's totally optional and you have many other options as well. In the future people will develop hundreds really different devices, services and tricks to store your coins securely. Compare that with monopolised non-innovative heavily regulated banking.
As bitcoins are so cheap to store, security is asymmetrical: it's much harder to take, than to hide. Gold, or any physical commodity, are as hard to protect as to take from you. Hence, most brutal guys end up owning precious metals over the course of the history. Average Joe can only have as much gold as he can hide in his pants.