If you want a single thing to use to understand the current status of the great experiment that is the United States of America, one needs only to look at who is allowed to vote. In the beginning, voting was neither and inalienable right nor a privilege bestowed from power, being instead the consequence of power itself. Wealth was the prerequisite for voting. And in a society where wealth was synonymous with the male gender and Northern European genetics, it set the stage for centuries of struggle to evolve into something better.

Today, voting is nominally universal; it is legally a civil right for all citizens, free from restrictions stemming from gender or race, or the ability to pay a tax or pass a test, practicable at the same age that makes you old enough to die for your country, and if you are residing out of state or overseas. But it was still hard to do in many places even before it became a political lever to promote authoritarianism with polling place distribution and shut-down-the-vote campaigns working to suppress the vote largely along race and class lines. Prisoners are largely not permitted to vote while incarcerated and felons face disenfranchisement even after serving their sentences. U.S. citizens residing in U.S. territories are not permitted to vote in national elections, and U.S. citizens living overseas who have never resided in a state (i.e., they were born to U.S. citizens overseas and have never established residency in a state) may or may not be permitted to vote, depending on the rules of the state where their parents last resided.
Enumerating the exceptions to universal suffrage – both on paper and in practice – and the trend they are following thus becomes an apt barometer to judge the health and vitality of the country as a whole. Voting is the one thing that tells you about a country, and who is allowed to vote is the one thing that tells you about voting. The difference between people of voting age, eligible voters, and actual voters is the one thing that tells you about who is allowed to vote.
For example, the 2020 Census reported the population of the United States at 331,449.281 people1, of those about 252,274,000 were over the age of 18, and of those, about 231,593,000 were U.S. citizens2. One of those two numbers is the how many people of voting age there were for the 2020 presidential election, depending on your view of whether or not non-citizen residents should get a say in how they are governed. 158,429,631 votes were cast in that election3, meaning that either 73 million or 93 million people of voting age did not vote for the president in what may be one of the most consequential polls in the history of the country. Even at the low end, considering only U.S. Citizens, 73 million votes is only about a million votes short of second place in the final tally.

In other words, when you count up all the eligible voters, then take “Did Not Vote” as a candidate, no candidate for president received 50% of the possible vote AND “Did Not Vote” received almost a third of the total votes. To restate again, in the 2020 Presidential election nearly third of voting-age citizens rejected every candidate on the ballot, either because they consciously decided they couldn’t be bothered to cast a vote, or because they were prevented from casting a vote for a reason not in their direct control. When you add that number to those who voted against Mr. Biden or Mr. Trump, voting-age citizens who rejected both the Democrat and Republican candidates or were denied the ability to vote represented the second place vote-getter. If you expand that to include resident non-citizens. this block won the election by over 15.5 million votes, or about twice the population of New York City.