Andrew: No amount of screening wil identify who among them are the potential future extremists and terrorists. Hasn't that been the case of those who migrated to the US onyl to create mayhem and carnage on US soil whn they hv grown up ?? Of course, for now they wil toe the line and express gratitude. But in this age of global connectivity, it wont be long before the radicals and extremists contact, and indoctrinate them, particularly the vulnerable ones who hv not quite made it in life, who are disillusioned. Don't put the security and welfare of the US citizens at risk for the sake of wanting to appear in good light in front of the world. World leadership shd not be had at the expense of the security of ordinary citizens.