It is a numbers game and the numbers are overwhelming.
In 2013 alone, 117,423 migrants from Muslim-majority countries were permanently resettled within the United States— having been given lawful permanent resident status. Additionally in 2013, the United States voluntarily admitted an extra 122,921 temporary migrants from Muslim countries as foreign students and foreign workers as well as 39,932 refugees and asylees from Muslim countries.
Now Obama also wants to add 10,000 Syrians. Consider the numbers on the next page: