if ETF and SEC not aprove, bitcoin can dangerous the future, poloniex, coinbase, bittrex can closed service , if ETF and SEC not aprove
An Exchange Traded Fund isn't a USA regulation.
It's a financial product that exists around the world. The US just decides to regulate such things for trading on their markets (i.e. the New York Stock Exchange, the NASDAQ). That US regulation doesn't prohibit any ETF from trading on the stock exchanges of the UK , Europe, China, etc.
This is a very important distinction.