The "best" part is how good an AI would be at privilege escalation. Go ahead, build out that security camera network, automate your cars, store your money using cryptography. I'm a geek and I love the way technology increases our collective prosperity, but most of our security relies on the attackers being approximately as smart as any other human. To a sufficiently capable intelligence, encrypted machine code is just as understandable as the most elegant source code. Once you fully understand something, anticipated edge cases are easy to find and exploit... every day we expand the capabilities of a future strong AI.