This is called conspiracy. [1] How intentional, motivated, and opportunistic you were, and what actions you actually undertook all add up to the offense you committed.

A random person saying they'll assassinate the president probably won't be a serious threat, but if you have military clearance, access to secrets, show intent to trade those secrets, and initiate communications with foreign powers then that's more than enough to prosecute. Saying you were "just joking" to scam some money isn't much of a defense.

https://en.wikipedia.org/wiki/Conspiracy_(criminal)