In a joke that made Brazilians cringe and forced the U.S. Olympic Committee to apologize, a USOC worker scrawled "Welcome to the Congo!" on a board in the organization's Rio de Janeiro media center for the Pan American Games.
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It is just one of reasons why some people hate USA, when you show more respect to the people maybe you don't need to worry about bombs, terrorists or fly.
BTW, I don't see any problems on "Welcome to the Congo", I am sure that Congo theres a very nice people and no problem to be compared with them, in my opinion is better than "Welcome to New York/America/Any USA place, let us see if you don't have bomb in your bag".