At the end of the first volume, Tocqueville ties together the great themes of the macro and the micro aspects of democracy in America in this account of the core dogma of the American creed, popular sovereignty.
Providence equipped each individual, whoever he might be, with the degree of reason necessary to guide his conduct in matters of exclusive interest to himself alone. This is the great maxim on which civil and and political society in the United States is based: fathers apply it to their children, masters to their servants, towns to the people the administer, provinces to towns, to Union to the states. Extended to the whole nation, it becomes the dogma of popular sovereignty.
Democracy is deep in the bones, the mores, of Americans, because we believe that individuals have sufficient reason to work for their self interest. Popular sovereignty is the sum of those individual reasons, at whatever level of organization we are working.
Believing that individuals reason sufficiently well to discern their own self interest is a dogma. Believing that society is well served by accepting whatever those individual reasons add up to is an even more daring dogma. These articles of faith cannot be proven. They can also be dangerous, which is why he spends much of the rest of the book talking about the useful restraints on majority tyranny. But no society can exist without dogma. This is ours.