Comment: Meanwhile, I hear in New York, the Islamic terrorist who ran over those people, had petitioned for 23 others to come from his country to America. If true, it's just another reason for more thorough vetting over who we are letting in America, before they are allowed into America. Once thoroughly vetted, fine, welcome. The world is changing, terrorism is now becoming evident throughout the world, even Europe wants to secure it's boarders and do more thorough vetting.
America, the worlds 3rd largest nation of over 350 million people, has enough problems with it's own violent criminals, we don't need to import them from the 3rd world without a thorough background check as well. Our quota in that area of need and skill expertise level is pretty well full. 
We have enough violent criminals in America as this Walmart incident and Las Vegas shown. Sad as it may be, the world has even more, with many who become radicalized and hate America deeply. It's very wise to know who we are letting in.