Originally Posted by Firebug4

The officer very likely will ask every time. That is because it is extremely unlikely that the passenger does not have his passport with him. As I explained earlier it is because usually the passenger needed that passport to get into the country that he was going to. That does not mean that it is an automatic secondary if the passenger doesn't have the passport. The officer wants the passport to stamp the admission stamp in. This is important if the passenger decides to naturalize later down the line because the stamps in the passport are one of the things that is used to determine if physical presence requirements have been met. However, this is becoming less important as computer systems continue to become more sophisticated.

FB