Let's suppose an American travels to another country and then, once receiving the hospitality of those people, openly criticizes and derides them, and defiantly spurns their laws and customs - do you suppose that country will continue to tolerate them? At the very least they will kindly escort them out of the country to make room for a more appreciative and thankful guest.

No matter what reason I go to another country, for love or family or occupational opportunity - if I have disdain in my heart for the country and customs and laws of the very people who are welcoming me into their home land, I am an ingrate, exemplifying the opposite of the true Christian virtue of humility. 

This IS the attitude of many (perhaps not the majority) who come to America today.