A better comparison would be bittorrent.
How's that been working out for bittorent? I'm sure government/lobbyists would just love to shut down bittorrent. They would love to outlaw it if only they could enforce the ban. But that ban would not be even remotely enforcible, and they know that. Drug laws are at least somewhat enforcible.
Also, bittorrent pisses off a lot more bigwigs, at the moment, than bitcoin does. Yet it continues to thrive, as it changes the world. I'm sure that when bittorrent first hit the scene, these same conversations were taking place.