i think nothing can destroy bitcoin easily. there has been a lot of problems in the past like in the beginning people didn't trust it and called it ponzi and later there were all the hacks, gox,... but bitcoin had survived all of them. so i guess in the future any problem is solvable, even if it is big.
I also hope that bitcoin will continue to survive all the problems, but at one point there must be a big problem, big sites like mt GOX turn out to be a scam., it was enough to make the price of bitcoin fell enough in, what if all the sites exchangers and wallet turned into a scam. of course it would be very detrimental for bitcoin