Of course, it already has been raised. Ron Paul has long made his position clear that drugs should be legalised and has made the argument forcefully. But the BBC will never mention his name. They don't want to confuse the British public by discussing a Republican who stands for peace, free trade, liberty and an end to US imperialism.
Fortunately the BBC no longer has such a grip on information. Gatekeeper it remains, but the wall is breached.