Bitcoin is known as to be the biggest cryptocurrency. in some countries it can be used to purchase goods and services and some see cryptocurrency as a threat.
if Bitcoin comes to be number one currency in the world today, can it be hijack by the government?
Hijack in other words steal? I don't think so. Unless government could access your hard earned private keys then nobody can ever access your cold wallets besides it is a crime. Furthermore, governments would probably be implementing regulations to cryptocurrencies and that would probably be worth something to them.