Let me avoid the technical aspects to make things easy for all readers.
So someone said that America's NSA has this great computer(quantum computer) that could easily hack Bitcoin private keys. I really doubt his claim but I know for sure that certain computers like the most powerful Super Computers are within the reach of some of this Intelligence organizations.
Do you think such computers can crack any security codes put in place to make Bitcoin very secure?
Bitcoin economy comes with big risks. Over the years, the Bitcoin world has been plagued by hacks, scams, and abusive practices. Users who don't take appropriate precautions can lose everything.
Here we present a short history of the Bitcoin world's most significant scams and hacks. It's worth noting that all of these attacks were against Bitcoin-related services, not the core Bitcoin software. As far as we know, the Bitcoin network itself is highly secure, though of course that's little comfort if you entrust your bitcoins to a third party that gets hacked.
Also, the list seems to skew toward older incidents. Users seem to have faced greater dangers of hacking and fraud in 2011 and 2012 than they do today.
Still, the dangers haven't gone away by any means. The Bitcoin economy is still lightly regulated, and fraud is a constant danger. While it might seem tempting to buy some bitcoins in hopes they'll go up in value, the risks are highperhaps too high for most people. If you do decide to acquire bitcoins, do your research and be careful.
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https://arstechnica.com/tech-policy/2017/12/a-brief-history-of-bitcoin-hacks-and-frauds/If you will look at the history of bitcoin the securities are increasing and increasing because of those hacking that happened, if there will be a way of cracking it will need a longer period of time before that happens, because those hackers are profiting too in this bitcoin world they won't just do anything that will make bitcoin crash without profiting first.