Harboring terrorist, sanctuary cities, what's the difference?

When President George W. Bush sent American forces in to Iraq to remove Saddam Hussein from power one main reason was to keep weapons of mass destruction out of the hands of terrorist and states that harbored terrorist. Syria, Lybia and Iran are known safe-houses for providing a gateway for terrorist to easily slip into Iraq. Here in the United States we are faced with a similar threat of safe-houses known as "Sanctuary Cities". These sanctuaries allow illegal immigrants to walk freely and does not allow for any local or federal officials to investigate their immigration status. August 4, 2007, in Newark, New Jersey, three college students were shot and killed execution style by Jose Carranza an illegal immigrant from Peru. Carranza was already freed on bail for 31 counts of sexual assault to a kindergarten aged child and also for an assault in a bar fight. These are terrorist that are on American soil. They cross the border, just as the terrorist crossing through Iran into Iraq, with intentions to kill, traffic drugs and bring with them various forms of weapons of mass destruction. How can a country, such as the U.S., allow this type of terrorist activity happen to occur on its on soil while fighting against terrorism on another countries soil. Is it solely for the votes that a presidential candidate is afraid that they will lose? Why is President Bush offering amnesty to the millions of illegals here? The majority of them do not contribute to the economy but rather send most of what they make to their families outside of America and never pay state or federal income taxes. They utilize our hospitals and never pay the bills they incur. Through the no child left behind act, they send their children to school and take away from positions that could be filled with children of U.S. families. They are destroying this country economically causing us to pay for the debts that they create and when these cities protect them they are harboring law breaking illegal immigrants. They have more rights than you and I and are protected by governing laws that do not protect you in their countries. The local government officials in these cities should be removed, just as Saddam Hussein was removed, for harboring illegals. So I ask you, "What is the difference between countries that harbor terrorist and cities in our own country that provide sanctuary to illegal immigrants"?