I've never heard an answer to this. If we want to cross into Mexico, we show our passport and walk in. The U.S I assume works the same way. What baffles me is this. Why dont the illegals trying to get in to the U.S crossing the river or with help of human trafficars just walk accross the border like we can and do ? Please inform me on this. Thanks.
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He who joyfully marches in rank and file has already earned my contempt. He has been given a large brain by mistake, since for him the spinal cord would suffice.

- Albert Einstein.