As a person who decided to join such a party of own volition, answered "yes" to that question in that form, and had to submit an accompanying statement, then proceeded to get US citizenship, I believe this particular bit is a violation of the first amendment, and would love the Supreme Court to struck it down. It violates the letter of the law, and probably the intent too. For all we know had the idea of communism existed in the late 18th century some founding fathers could have subscribed to it.