The only thing that can destroy bitcoin is if somehow the internet were to become dominated in some way. If ISPs could control traffic, so that they could allow things they want and disallow things they don't want, that could really threaten bitcoin. If the government somehow took over the internet or regulated it's use in the same way that ISPs could hypothetically, then that would pretty much shut bitcoin down as well. I don't think these scenarios are possible, and becoming even less possible as time passes. Many projects are in the works for an entirely decentralized internet as well. There's really no stopping it in my opinion, but people will try their damnedest to hold their ground.