“How can the sovereign, which is The People, remain sovereign under a powerful Executive? The Executive himself must acquire sovereignty via heredity.”
Um...the People remain sovereign via elections, and the checks and balances provided by a three-fold government. We do NOT remain sovereign by right of having a President born in the USA.
What was it the original citizens called perpetual allegiance? "Perpetual nonsense." That is what you'd have the same people use as original source for their own citizenship, lol.
A sovereign people cannot be led by anyone other than themselves and that occurred via descent, just as a monarch could not be sovereign without that right descending to him.