This is the most question asked everyday 
). There are noway to kill cryptocurrency and nobody can do it although they can find out any way ). But I think the only thing can kill cryptocurrency is cutting of electric all over the world forever. LOL. But I think it'll never happening. Beside there are some prediction that cryptocurrency can survive till 2140 when the last Bitcoin mined out.
Internet should be one factor too,if theres no internet how would you expect those blocks to be confirmed? it is really hard to predict if how long these cryptocurrency ear will last as theres a lot of countries regulating cryptocurrencies,theres no assurance or gurantee to what our market's position to the whole world,though it is a question that frequently being asked here theres still no definite asnwer yet.). There are noway to kill cryptocurrency and nobody can do it although they can find out any way ). But I think the only thing can kill cryptocurrency is cutting of electric all over the world forever. LOL. But I think it'll never happening. Beside there are some prediction that cryptocurrency can survive till 2140 when the last Bitcoin mined out.