You folks need to volunteer to run an election sometime so you can understand how an election is secured. I am a volunteer poll worker in Virginia. We use a deep defense-in-depth strategy to protect against fraud. Fraud is a non-trivial problem that is technically difficult to solve, because it can take so many different forms and because there are so many people involved. We are dead serious about election integrity, and at least in Virginia, we do hourly audits as an election proceeds. If we are off by even 1 voter in our audit, it is a major event with an immediate inquiry.
When I read about Russia sowing distrust, I nod my head because not many people understand how elections are run. It is easy to be distrustful of something you don't understand. But when I read about Russia actually being able to do anything material to effect the counting itself, I laugh because it would take such a massive effort that it would actually be easier and more reliable to just use normal bribery to get what you wanted. Something like the Clinton Foundation is the way to do it, that's a marvel of efficiency in terms of hooking up money with political outcomes. Even better that it stays just on the right side of the line, legally (well, at least "provably", which is really the crux of the matter.)
One of these days, I need to write that book on the election process. I became a volunteer more than a decade ago after reading one of these articles on hacking voting equipment. I was curious about how feasible that really was, and was very, very impressed with just how difficult it would be to actually do it.