That's great, you linked something specific to talk about. Interestingly, the actual application of that law demonstrates how rights are protected in the US. You may know that Chairman Xi thinks there should never be an independent judiciary in China. So the vague national security law there ends up as nothing but a tool of the state to arrest those it doesn't like.
In the US, the Supreme Court balances that law against our constitutional rights, rendering it almost unenforceable. In fact, the way that law is applied is very specific, not vague at all.
Please read: https://en.m.wikipedia.org/wiki/Yates_v._United_States
Nathan Rich and people like him may be fun for you to watch because they confirm your worldview and reinforce your biases, but I suggest you read some real legal scholars if you're interested in actually educating yourself.
Edit: Also, getting back to the origin of this thread, nothing in US law prohibits what Jimmy Lai did. And nothing prohibited it when he did it in Hong Kong. Even besides how disgusting this law is, applying it retroactively is truly appalling.