Whether Domestic or Foreign hacking is destructive. If hackers are good enough they can bring the US to its knees. Are y'all worried? Why?

Not so very much.
It is a funny thing but here is a situation where privatization is clearly less effective than having the government run things. You need a whole lot of coordination to discover and backtrack hacking to find the actual hacker.  Such coordination is a lot easier for a government department than it would be for a lot of competing private companies who has to be careful about every word they say to each other so they dont accidentally reveal their methods to 'the competition'.

i try not to think about it since theres not much i can do about it