i think US already Create their own crypto. what we call (xrp) ripple a US based technology company. when they first lunch this crypto theysaid xrp can kill BTC.
In what way? Shoot a nuclear missile right at Mr. BTC? Or send a squad of security forces to close the servers of Mr. BTC?
Who and what will replace what is not decided by the companies that put forward their product - it's just their wet dreams. This is decided by the people, the end user, who is the direct consumer of any product produced. And something I don't see any trends for XRP that it would just take and "replace & destroy" BTC. How do you imagine this?