@Frank Apisa,
Your right, the last part of his sentence makes no sense.
He is also wrong on the "clear and present danger" part. From what I read of what he posted, if the talk of a forcible overthrow of a government is an abstract idea, then it is not illegal. I guess if you just say, "I think we should overthrow the government" but then don't follow up with actual plans, then you are ok. But if you then follow up with plans, then it becomes less abstract.
Moreover, since the Patriot Act, which I confess I have not read at all, that may have changed.