Ever heard the word eco-terrorist. That is most assuredly one group, PETA comes to mind, there are many others and they are indeed citizens. The Uni-bomber would be another as would the recently caught Atlanta bomber another. Hardcore Demo-crats, leftists comm-unists, and ideologies we may not even be aware of, have sufficient desire and reasons to advance their agendas in any way that brings about the desired conclusion, the destruction of the United States of America as the Founding Fathers saw it.
Are you suggesting that these fringe groups are representative of the politically active and opposed in the USA? Or that this excuses immigrants there conduct and behavior? i don't see where your argument is going?