> It was enacted partially in recognition of the thousands of Native Americans who served in the armed forces during the First World War.

Historically, it has been warfare that seems to have driven a large part of democracy and enfranchisement.

An example that is brought up is the Athenian navy. Because they relied on lots of common people to row, it shaped their political system to favor democracy over the more elite Spartans.

The downfall of feudalism may have had a lot to do with mass infantry and/or archers showing their worth versus elite mounted knights.