Bitcoin has high fees and is slow. It does not even work as a cryptocurrency, companies are stopping to accepting it due to how inconvenient Bitcoin is. Bitcoin is a dinosaur to many other cryptocurrencies and I hope it dies soon, there's a lot better altcoins.
If you believe that BTC limited supply gives it value, it's good for large transactions like paying of international debt.
I'm sure US, China, India, Korea and Russia will be using it and mining it, for exactly that.
There are a lot better altcoins i agree. Bitcoin will be hard to kill though, its the gateway cryptocurency for the most part. Its tradable with almost any coin on the market. My current favorite cryptocurrencies to invest in are Ethereum and Neo. They offer real value services instead of just being a store of value like bitcoin.
If Bitcoin DIE, it's like you said the US DOLLAR die also.
The center for CRYPTO is BITCOIN! Same with the US Dollar.