I've done a lot of international travel both before and after 11 Sep 2001.
A comment above stating something to the effect that, an asshole is an asshole, regardless of neationality is so true.
An incident in Greece in '97 made this very clear to me. A Greek woman in Athens made a very rude attempt to cut in front of a long queue of people waiting for taxis. When I pointed out, politely, that the end of the line was several steps back, she began shouting and used the infamous, "ugly American." I try to be sensitive to local cultures and customs, but she was simply rude. Otherwise, I haven't been to Europe since then.
I travel as adventure, to learn about other cultures and people. I'm not conspicuously American (you can tell Americans by their shoes
) and have often been mistaken for French, which I speak nearly fluently, or German, but I have a much better sense of humor
As far as the fear factor, I guess I'd say that for me it's more of a realistic amount of caution rather than fear. I don't expose my passport until I'm at the desk/window of the customs agent; I remain very aware of my surroundings; I don't frequent typical local sites, rather opting for out-of-the-way destinations, etc.
Even if I go to countries that may have issues with Americans, or peripheral fallout from civil strife, I'm rather low key: I'm there as a tourist and a guest.
I was in Rio de Janeiro in Aug 2002, and the tourism -- even for the low season -- was incredibly depressed. Brazil generally has no problems with Americans or the US, but the local crime and political problems were something I was hyper-aware of as a someone travelling alone with only a limited Portuguese vocabulary to get me by.
In Nov 2003, I was in Singapore and Bali. Singapore has a large number of Muslims and sentiment seems to be mixed toward the US and Americans. I felt not only safe, but a bit "under the microscope" in that the government is even more Orwellian than our own administration. Bali was still reeling from the bombings and tourism was still down more than 50 percent. Friends and I stayed in a completely different part of the island and security was incredibly tight everywhere. Bali was targeted primarily because of its Hindu majority in a Muslim-dominated nation and it just so happened that a large number of foreigners were there as easy, drunken targets.
On Sunday, I'm headed to Singapore (I have American friends working there, a gay couple), and we're going to travel through Cambodia and Viet Nam. I don't anticipate any problems. I'm a sightseer and guest, and I act appropriately.
Of course there's always a bit of concern, but should I be more worried about avian flu or anthrax? Street crime or a suicide bomber? Jet lag or politcal communism? Montezuma's revenge or Islamic jihad? It's all relative, and while I'm cautious about it all, it's really no different than living life in my own city.
There are lots of other places I want to visit, including Iceland, the Scandinavian countries, Argentina, Chile, Peru, Scotland, India, Costa Rica, etc. And when I do, I won't be afraid but I will be cautious.