What's funny is that many changes were pretty fundamental legal changes, such as the abolition of slavery, massively extending the right to vote, allowing a wide range of pornography & allowing abortion & contraception. To claim those as "merely updating our understanding of what the founding fathers wanted" is misleading, but eh, if it makes you sleep at night.
I'm not sure how you could call those changes "fundamental". Some of them were pretty far-reaching in terms of resulting impact, but they did not fundamentally alter the Constitution.
They altered US society in some pretty massive ways, altered who controlled the government, and had large and fundamental impact on many people's lives.
Well, that's a debatable point. What is the core concept? That the people should elect the government? Well it went from white landowning males electing the government to all adults (excl. prisoners)? Does that count?
