This is exactly what makes the US constitution and its relationship to the Supreme Court so bad. It's up to the 9 people on the Supreme Court (who were all put there for partisan reasons by whatever party was in power when their predecessor happened to retire or die) to decide what the intent of the founding fathers was with the Constitution. Because obviously it says nothing about abortion, nothing about modern weapons, nothing about internet surveillance, etc. They get to decide. And if you happen to get three picks in your term, like Trump did, suddenly everything changes. Biden and the Dems in Congress can win 70% of the vote next election, and it still wouldn't alter the fact that those three people are going to be there for decades to come, deciding. In a democracy.
It's just a bad system. It might well have made perfect sense in the 18th century, but since then other countries have figured out better and more up-to-date ways of doing things.
Edit: I'm not an American, I'm just upset like one.