The largest and most sophisticated holders of crypto assets would be using multi signature wallets with a protocol between multiple private and secure participants. How does a gun allow you to seize private keys? We are back to they can threaten to kill you? But there is a problem, if they do they lose the keys also. Guns and weapons are massively less effective against crypto assets in comparison to traditional assets. If one owns a factory and doesn’t pay taxes, those guns work very well in comparison.