I travel to the US a fair bit (for long stints so its not yay yay holiday holiday time all the time) and Ive visited various areas (DC, Baltimore, Parts of virginia and maryland, Florida both east west north and south etc etc)
Americans are some of the most hospitable people your ever likely to meet. On the whole they remind me a bit of children at times. They are nieve and not 'damaged goods' like many europeans (particularly the french) are when it comes to meeting people. They dont tend to mistrust you or think bad of you just based on where your from. Most of them embrase you with open arms.
The warmth i have yet to find elsewhere in the world bar maybe Britain. There is very little 'snootyness' which you find on the continent. (not all the time but you know what i mean by this if youve ever travelled around europe. most are nice but theres a fair number who act like you are satan himself if your not a native)
The problem many europeans have is not actually with Americans themselves but with America as a whole. It is not the way of life. It is not the vast military might or its massive economy. It is the way in which American ideas and 'way of doing things' has been pushed upon the world. The foreign police of the United States has been both hypocritcal and driven by highly conservative politicans backed by large corporations (in itself a suspicous coupling of politics and money).
Europe itself was once the most powerful and feared continent on Earth. Noone dared stand in the way of European supremacy. Along with the French, Germans and Spanish we British conquered half the world and laid waste to anyone who dared oppose us. Those days have past. World Wars 1 and 2 made sure of that. European military might was decimated and instead we relied upon America whilst we rebuilt.
This has led to a somewhat odd relationship. America continues to protect europe with its powerful military. It offered unreserved protection during the Cold War and continues to provide the 'attack on one is an attack on all'. For britain and france this may nto be a huge issue because of nuclear weapons. However America is still there and steps in when we decide to fight a battle. Noone dares threatens Europe in any real sense because we are fundamentally protected.
However the protection of modern times is somewhat different and irrelevant to the protection offered during the cold war. During this period Europe rebuilt its economy (as a whole) and blossomed into the Economic giant we see today. America stood by and encouraged europes capitalist free market tendency so it could create markets for its own goods. As Europe recovered few nations rebuilt their military. Why bother? America was there with all the guns and they were willing to protect us.
Robert Kagan wrote an increadibly interesting article regarding all this. He stated that Europeans continually critisise American foreign policy in particular because of its aggressive nature and of its 'arrogance' and 'brashness' yet seem to forget that not so long ago europeans were also spreading their empires across the world in pursuit of domestic goals. Those with power use it. Those without complain about its use. Europe is also in a rather interesting position. It has been allowed to flourish with a 'safety' net around it during the Cold War. THere was little chance of Soviet invasion when US nuclear missiles were aimed as Moscow. America stood by at the gates of europe with a giant sword whilst the European countries within were free to pursue an economic agenda free from fear which now sees us with increasingly strong economies (as a whole) but without any kind of real military power.
Our safety allowed us to talk about things such as 'diplomacy' and 'fairness' when in reality not a huge amount of what goes on in the world is fair at all.
When has a country ever not used its power to ensure its own people continue to live and fulfill the expectations they have?
I cannot think of a single world power which has not exercised its power to its own advantage even if the rest of the world frowns upon it.
As such America is disliked. Europeans want more diplomacy and less 'trigger happy' responses. America obviously doesnt see the need for diplomacy. But why would it. It holds the biggest gun in the entire world and theres noone there to stop it using it.
The old 'balance of power' has gone leaving a unipolar world where one country has free reign with no real counterbalance to its huge power and aspirations. Noone to keep it in check and noone who can forcefully say 'No.'
America has continually vetoed sensible UN resolutions regarding Israel.
America has broken International law numerous times (Cuba is a perfect example with the 'detainees') and continues to act in a way that makes many nations uncomfortable.
This is the country. This is not its people. Any nation with the amoutn of power America wields will always be hated. It is capable of ensuring its wishes are carried out. Europe can not lay claim to such a concept. IT cannot 'force' its will on others. America can and does.
As such it breeds resentment.
Thats on the whole anyway. The other reason why many "americans" are disliked by the world is much to do with the American media. Fox News in particular has done America no favours on the world stage. Highly right wing commentators spouting 'we are the most powerful country in the world. do you really think we give a damn what you think' or the classic 'Canada should be happy we even allow them to share the same continent with us - ann coultuer'.
These kinds of comments inflame people. Instead of seeing them as the thoughts of one highly right wing loon they believe many more think the same. Everyone of any intelligence in America who i have ever spoken too takes these people with a pinch of salt. OF course americans are patriotic etc which usually comes across as 'nationalistic' and OTT (flag waving here we come) but im almost sure no harm is meant by this.
Anyway. Read the article by Robert Kagan (i got it wrong before).
IT can be found
http://www.policyreview.org/JUN02/kagan.html