For a fully-capable sophisticated AGI, the question is surely trivial and admits of many, many possible answers.
Could the NSA, the security agency of the most powerful country on Earth, implement any of these schemes?
The NSA not only has thousands of very smart drones (people), all of which are already equipped with manipulative abilities, but it also has huge computational resources and knows about backdoors to subvert a lot of systems. Does this enable the NSA to implement your plan without destroying or decisively crippling itself?
If not, then the following features are very likely insufficient in order to implement your plan: (1) being in control of thousands of human-level drones, straw men, and undercover agents in important positions (2) having the law on your side (3) access to massive computational resources (4) knowledge of heaps of loopholes to bypass security.
If your plan cannot be implemented by an entity like the NSA, which already features most of the prerequisites that your hypothetical artificial general intelligence first needs to acquire by some magical means, then what is it that makes your plan so foolproof when executed by an AI?
Two major limitations the NSA has that AI does not:
1) The NSA cannot rapidly expand its numbers by taking over computers. Thousands - even several dozen thousand - agents are insufficient.
2) There are limits to how far from the NSA's nominal mission these agents are willing to act.
Any scenario where advanced AI takes over the world requires some mechanism for an AI to leverage its position as ethereal resident of a computer somewhere into command over a lot of physical resources.
One classic story of how this could happen, from Eliezer:
You can do a lot of reasoning about AI takeover without any particular picture of how the world gets taken over. Nonetheless it would be nice to have an understanding of these possible routes. For preparation purposes, and also because a concrete, plausible pictures of doom are probably more motivating grounds for concern than abstract arguments.
So MIRI is interested in making a better list of possible concrete routes to AI taking over the world. And for this, we ask your assistance.
What are some other concrete AI takeover mechanisms? If an AI did not have a solution to the protein folding problem, and a DNA synthesis lab to write off to, what else might it do?
We would like suggestions that take an AI from being on an internet-connected computer to controlling substantial physical resources, or having substantial manufacturing ability.
We would especially like suggestions which are plausible given technology that normal scientists would expect in the next 15 years. So limited involvement of advanced nanotechnology and quantum computers would be appreciated.
We welcome partial suggestions, e.g. 'you can take control of a self-driving car from the internet - probably that could be useful in some schemes'.
Thank you!