Many things factor in an answer... We have Ego because we think we are separate beings. We think in separation, we think in division Too many material attachments desires for sooo much too little spiritual values awareness is of the material world no awareness of the oneness of life only awareness is of division, of separation from oneness as a separate being. Of course all that exists in varying degrees across the Earth and with each person.
Some are, some are not. I think it is easier for many of us to have in this country lives full of goods both material and spiritual, lots of love, success, the ability and wherefor to realize dreams so we quite take that for granted. And when we don't find the same environment elsewhere we simplistically conclude that our country must somehow be superior. So too there is sort of a sports mentality of "we're number one" that seems very pervasive among us. It disturbs me that many Americans, in roaming the world, just assume they are above following and paying respect to the customs of whatever country they are in. Which shows a lack of respect. Somehow they think being American gives them the license to just override them. Which is wrong. Many people are jealous of us - but if we want their respect I think showing them respect would be a good beginning.
Nationwide chauvinism with the military and economic firepower to back it up. The US knows it can get away with the most outrageous chutzpah because of the devastating consequences of objecting to it.
Beats me! I have heard that it's partly cultural, going back to the beginnings of what we now know as America, the belief that god had provided this land and the idea of the land and therefore the people as being special.
Some would argue it's poor breeding, a lack of class that leads one to boast, be loud and boarish without seemingly knowing or noticing the result. Some might say it's cultural and arguably perhaps that Americans are encouraged to stand up for themselves, to be proud etc.?
I don't know.. I prefer to take people as individuals rather than generalise... some do, some don't - there are tendencies but would be wrong to tar all with the same brush.
