A general question clicks in my mind, that there are many ways to bypass the security.
So, what is the highest degree of security?
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I think the fundamental problem here is that "highest degree of security" is a nebulous concept. Security isn't an absolute, but rather a game of give and take. It is about trying to balance acceptable risk vs difficulty in access.
The systems that are generally considered the "highest" security by the public would be things where physical security plays a key role. These kinds of government systems are not physically connected to the Internet, operate on their own private, encrypted network and the only locations with access to the keys have armed guards and multiple redundant physical systems preventing unauthorized access to get to a terminal that has access.
You are however correct that an attacker with unlimited resources and unlimited will could potentially bypass any security. This is why the highest degrees of risk mitigation rely on many overlapping factors to provide as complete of protection as possible.