I grew up overseas and I don't see much difference here than many other places in terms of nationalism. Everywhere I have been has had people who have been proud of their country and others who are disgruntled by certain aspects. And in terms of the US, look at Texas for example - they are pushing for a Texit!
There are a lot of people here in the US who do not agree with many things our government is doing. But the everyday person doesn't know what they can do to change anything.