Earlier quoted context omitted.
It means that anything not expressly prohibited in the constitution is up to the states to decide. What most people don't get (even in the USA) is that the constitution doesn't grant powers to people. It only restricts the government from acting on the people. People were born with the right to speak freely and defend themselves as they see fit - the government can't change that for example. So the 10th says if it is…
On what is this analysis based? No offense to the parent, but I've learned that analyses of law by non-attorneys, while they can be valuable in regard to principles, are about as accurate as an attorney's analysis of a software project.
Feel free to reply to him with your expert analysis that contradicts my simple overview.