The Founders were concerned about the likes of Maximilian I of Mexico.
Never in their wildest dreams could they have imagined that a traitor such as Obama would surface and twice be elected President!
There is no way to write a filter into a constitution that would reliably filter out such vermin.
That's true. Process will only take you so far.
In the end, it's the sovereign who must prevent any usurpation.
And of course in the United States, We the People are sovereign, under the Sovereign God.
The election of Obama demonstrates a very dangerous degradation of the moral character, wisdom, and understanding of that sovereign.