bitcoin is not so strong enough in case of security and it can be hacked as it happen during the bitfinex attack. well the bitcoin is so strong that it can run without any government people and it can totally by itself for the world to keep going.
The security problem in Bitfinex attack is not related to bitcoin. In this case the bitcoin was not hacked. Hacking was done on Bitfinex systems.
Such hacking events can occur for all payment systems. Bitcoin is a secure system based on existing infrastructure.
As far as I know, there is no weakness except for the 51% attack.