To speculate such betrays one’s lack of knowledge of how they work. They are cryptocurrencies BECAUSE they cannot be manipulated. Study Bitcoin structure and learn… certainly before you attempt to buy.
And you don’t need internet to trade bitcoin. Two individuals with working computers can trade bitcoin between themselves. So it’s just a matter of keeping a shielded computer safe and disconnected in a can to survive an EMP. Solar electricity, anyone? Bitcoin can be locally traded if a shop keeper is equipped with a computer and BTC wallet software.
My greatest fear with Bitcoin is the attempt to get approval for an ETF of Bitcoin. The largest hoard of Bitcoins I have read about are owned by the Winklevoss twins. They are wannabe Bankster Wall Street types who have applied for a BTC ETF with the backing of their hoard. The SEC just turned them down, and I hope it never gets approved. At that point, financial ‘paper’ manipulation enters the scene, and I would likely dump out.