"Let's say their methods are questionable in that they trespass - is that ALL? - and cause potential - not actual - danger to life and operations."

Well, for starters, the article actually points out incidents of violence, vandalism and destruction of property, so it's a little more than simply trespassing . Secondly, if you keep causing potential danger to life and operations often enough, sooner or later that potential will be realised.

I'm all for protesting something you are opposed to, but when you veer into criminal territory, you should be treated like a criminal. Or would it be OK for a homeless person to trespass on your property, because they have nowhere else to go, and are only causing 'potential' danger to you and your family?