Apples and oranges.
Switzerland has several characteristics which render its situation qualitatively different from that of the United States. Switzerland is much smaller in terms of geographic size and population, and there is also a much greater degree of ethnic and cultural homogeneity. The United States was also a growing nation with an expanding frontier which incorporated new territories periodically.
Having said that, your thesis isn't necessarily false, but the prevailing conditions in Switzerland—versus the United States—were sufficiently different that similar outcomes couldn't be automatically expected.
Having said that, your thesis isn't necessarily false, but the prevailing conditions in Switzerlandversus the United Stateswere sufficiently different that similar outcomes couldn't be automatically expected.
This is odd, because it was from Switzerland that the framework of our own ideas of Republicanism emerged. Vattel put forth the idea that a collection of states could unite and form a Republic. We even borrowed their word "Citizen" instead of using our own well known term "Subject."
In 1776, the only other Republic in the World was Switzerland. All others nations were monarchies.