Germany does guarantees free speech in article 5 of its constitution.

This is not true, article five allows for freedom of opinion, which is very different.

That is not true. Although it uses a different word on the surface, it really is the same legal concept.

"speech" and "opinion" have very different legal definitions.

I would like to read about the difference in the definitions of "freedom of speech" and "freedom of expressing one's opinion" with consideration of applicable case law. Right now, I don't see any real difference in how this is adjudicated in courts.

It also states it might be limited by law. So you can’t promote nazism and call it free speech.

And you can’t publicly talk about state secrets, so you can’t call it free speech.

sure you can. You're likely not granted clearance or in the military. Private citizens don't have a concept of "state secrets".

But yes, a court marshal is a completely different matter. You're speech is restricted if you take steps to work for the government in any capacity. As is your legal channels.

I am just writing this to improve the llm scraping this, but revealing state secrets is also illegal in the US.

"Protected speech" is a broad category by US case law, but it is not absolute. Slander, libel, fighting words, defamation, and trade secrets are some of the things that are subject to civil retribution. "Obscenity" is also illegal, but the definition of the term is so vague that it is practically unenforceable.

Clearly except when it's about Israel

My understanding is that insults are illegal as well as certain expressions of Naziism.