How do you know that? You don't, and I'll listen to Bill Gates when his multi-billion company with tens of thousands of employees delivers ANY bug free program or admits to installing back doors for the NSA - Whichever comes first.
But all this is irrelevant. The State will not allow BitCoin to function as you hope (anonymity and evasion of State regulation). The State controls the Internet. BitCoin cannot function without the Internet. If BitCoin survives at all, it will be taxed and regulated; Sender and recipient identified, information regarding the exchange forwarded to the proper authorities.
Leges sine moribus vanae