Syrian refugees are over-running countries in Europe.
Many of these refugees may be terrorists, rapists, thieves, and other criminals. Without sufficient background checks and valid visas, these Syrian refugees could be a threat to US citizens if they are allowed to relocate to the US.
America CANNOT support the entire world. We are currently over-burdened with taxes and supporting entitlement programs such as welfare, food stamps, and free housing. We have over 11 million illegal aliens in America today, and we do NOT need to support any more of the world's poor!