[MannoFr]

That is a function of the government, and probably will not happen, especially if the group has been infiltrated. The government may want to gather information for possible prosecution or other useful intel. These groups have free speech rights that should not be abridged. Others also have the right to report on these proceedings as their own personal agendas or biases dictate. The speakers may just be blowing smoke or voicing wishful thinking, and even if they're not citizens, they are allowed these freedoms up to a point (if violence doesn't break out as a direct result of their speech). If their statements reflect poorly on the community as a whole, then the community needs to confront them personally. I say, let them speak, and even though I may disagree with everything they say, I can gain insight from their words and body language if I am able to see the presentation (which at times can be found at other links).