Bullshit, stop giving them so much credit for things they never were involved, SHA-256 is an algorithm which works by mathematics and has nothing

To do with US national security agency, we know US is an advanced and a technological super power giant but this is different, I'd say they are doing

The opposite of  keeping their people fat and safe if they were actually behind Bitcoin and blockchain technology, if you have doubts then either buy

As many as you can afford to or get out before they come for you  .