Anyone who travels overseas has to be aware of the fact that Americans are not always popular. I was astonished in Berlin a few years ago when a young man went way out of his way to help me when I became only slightly turned around in a large shopping mall. I simply assumed that he was a scam artist or pick-pocket, so I gave him a cursory "thank you" and quickly headed off in a different direction, trying to look like I knew exactly where I was going. I learned later from a Berlin resident that there is a sense of gratitude towards Americans dating back to the Berlin Airlift in the late 1940s. This is not the case in other areas of the world.
Particularly during the terms of our 43rd President, I sensed some negative reaction when people learned that I was from Texas. Even the Japanese, who are known for their meticulously good manners, would ask me what I thought about our President. I had to carefully craft my response. I will never forget arriving in Narita airport and looking out the window of the taxiing aircraft, seeing a bed sheet affixed to one of the buildings just outside the airport property with block letters saying, "PRAY GOD STOPS BUSH'S WAR."
Sometimes you may be compelled to be a little subtle about your citizenship. I do not advocate going to extremes as Lisa Simpson did in Italy when she pretended to be Canadian. However, you should not make the mistake that Homer did in loudly professing his American loyalty. I have seen seasoned business travelers who put American flags on their suitcases, computer bags, etc. That seems imprudent to me...but honestly, I have seen these same "seasoned business travelers" complain loudly that the air conditioning was not cold enough or that they needed a menu in English or that the taxi driver did not understand the words "Hilton Hotel."
When overseas, I do a few things to keep my profile low. I learn a few words such as "Hello, Thank You, Good-Bye." When I need to get to a location multiple times (such as my hotel), I print off the web page in the local language or get the concierge at the hotel to give me the name written in the local language. There are a few tips you can pick up along the way. For example, one of my friends lived in Tokyo and told me that I will rarely get a taxi driver who understands the words "Hilton Hotel" no matter how loudly or slowly I repeat it. However, the words "Hee-Loo-Tone Hotel-oo" works every time...it does. A few years ago, I was attending a conference at the Opera City building in Tokyo. "Opera City" does not work. When I started saying "Oprah City," the taxi driver took me there with no problem.
When I go to a store in almost any country, I find the screen on the cash register which will show me the amount due and therefore do not require the cashier to tell me in English. I can pay them, say "Thank you" in their language and they simply assume I understand some of their language. It makes me look like less of a fish out of water. Don't set yourself up to look helpless. That is good advice anywhere, but particularly when visiting a city far away from home.
And finally, read-up a little on the culture and on what is standard. The Internet is a wonderful thing. Learn about bowing in Japan and gift giving. Talk to other people who have travelled to Taiwan to find out if it is reasonable to pay $45 for a car from the airport. I paid $15 for a taxi from Beijing Airport to the hotel, but on my return trip, my Chinese friend only paid $7. I got ripped off! Learn about tipping. You can not force a bellman to take a tip in Japan, but just about everywhere else, they expect a tip from an American. Don't tip 15% for a meal in Germany. It makes the locals mad because they only tip a "pocket change". They say that we Americans make them look bad.