It's not entirely true to say we aren't a democracy in theory. In the purest legal sense, yes we aren't, but in the academic sense, democracy doesn't simply mean rule by the majority anymore. The word democracy is an ambiguous and contentious term in academia. Some scholars define it precisely as the Good Doctor has described a republic here. Further, we still do live by majority control. The constitution can be amended by a virtual 75% of the people through their representatives; thereby changing, e.g., Article 1 Section 8, with an amendment by a super-majority.
"A true competitor wants their opponent at their best." Lao Tzu
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