During a missions conference in San Diego, a few of us took advantage of a free afternoon to go sightseeing in Point Loma. One of the attractions is the lighthouse with a spectacular view of San Diego, Coronado and on a clear day, Tijuana. While hanging out there, we observed a small group of people chatting together. As we passed by, we thought we heard a smattering of Portuguese. Stopping and covertly eavesdropping, we heard the distinct lilt of that language.
Approaching the group, I asked, "São brasileiros?" (Are you Brazilians?). "Sim. Somos" (Yes we are), they answered with some surprise. Then one turns to the others and says, "Puxa, tudo mundo fala português aqui nos Estados Unidos." (Wow! Everyone in the United States speaks Portuguese!) Well, not exactly. But it was nice to make this group feel welcome.
I've always felt that interactions with other cultures require respect, humor and the expression of warmth. My first experience in Brazil was certainly a welcoming one. However I still distinctly remember the large handpainted graffitti spread across a stone wall in Rio de Janeiro: "Yanqui Go Home!"
It's certainly understandable that the sentiment exists. Not only for the economic realities of a nation suffering from hyperinflation and being seriously indebted to US and world banks (to the tune of gazillions), but also in the way that Americans conduct themselves overseas.
I've been on the São Paulo metro and city buses when groups of Americans have come on board. Loud, ill-mannered and oblivious to those around them. Young people rushing to beat older passengers to seats - in sections reserved for the disabled and elderly.

Loudly commenting to each other, "What a dump! This country sucks big time!" without a sense that there might be people who understood their English and could be offended by their rude opinions.
Respect and courtesy. It turns out that you have to teach it. There's a certain insularity that seems to happen to Americans in groups in foreign countries. It's like they're in a bubble that somehow shields them from their surroundings, and they feel that no one can see or hear them. It's unfortunate that public behaviors can result in private opinions about Americans in general. Of course, this is what I'm doing right now.
It may have been insulting to the young people recruited to serve on our ministry teams, but it was important to instruct them, not only about spiritual or cultural realities, but also about giving people respect and dignity. Perhaps it's due to the fact that many of our teams were composed of bi-cultural people who had experienced the lack of consideration by the majority culture in the US, that they understood and picked it up right away.
The title of the 1958 classic novel The Ugly American coined the phrase that now is used universally to describe the stereotypical bad behavior displayed by some Americans when dealing with other cultures.
It was good that I saw that "Yanqui Go Home" graffitti on my first trip to Brazil. I think that subliminally and later, consciously, it would impact the training and instruction that would be provided to our groups who represented not only Christ, but the USA.