What I find interesting, in this decent question, is it often brings out the "I hate America because" people. What I think people confuse Patriotism with is Narcassism or Jingoism, which there are many people out there like that, but that's not the question you asked. But I think overall, the majority would be a patriot called up to defend their country, not just in a war but through words, debate and positive action.
Being a Patriot and standing up for your country's core values is important. It's a very cultural thing in the US. "Proud to be an America", "Born in the USA", "Made in America", etc. We are a young country, born out of rebellion, we are less than 250 years old. We also became a very powerful country, very quickly, with our industrialism and powerful military, we became leaders in the World. This is why many countries tried to emulate the US and in some case still are.
What I think people focus too much on, is where we are at today, or what we've done in the last 10 years. There is a lot more to a country than it's latest act. Anyone older than 30, remembers the 80's, when there was the cold war, and it was the US vs. the USSR, people were taking sides to some extent. Outside of the 50's I suspect that was such a high period of pride and capital excess that made other developing countries want to be like that. We focus so much on our mistakes of the last decade that they also forget some of the great things done in the last 250 years that lead to the US being what it is today. We may bend, we may sway, but I think the core values are still there. I surely hope we still stand proud and can be a top country in the next 20 years.
Why do kids say the Pledge of Allegience? Why not. Why can't you say you will be allegient to your country? People forget not long ago there were too many questions about such things. Allegience isn't blind obedience though. Not doing so, could easily lead to destruction of the country from the inside. And though people may think that is a good, I don't we are ready to start over.
Freedom and liberty, are traditions in the US that you don't get everywhere else. I am talking in the grand scale not isolotated incidents, which I think occur everywhere, but the US has so much openness all warts are shown. We can't hide anything. You may think that US is heading into a bad direction, and I may agree, we have a lot of things to fix, but some can't be fixed over night. I get a bit miffed when people talk about problems, without offering solutions. So point out a problem and a suggestion, but don't think there are only problems. My goodness, look at all the good the US does. It's great that we can bring them to forefront and addresss them. So people over 50 still remember their parents talking of WWII, and during thar period pride swelled, industralism flourished, scientific discoveries were numerous. The US has done a lot of good things in the past and still do today, but people would rather focus on the issues or in many case focus on the superficial (Top news stories are Michael Jackson's Dr., Lindsey Posing Nude, someone having a 20th kid) and it drives me nuts..
So in the end, the US is a proud country and will defend her. I think some of it, we think we are the protector, big kid on the block, so we believe we have to put on a good face. But really, there is a lot to be proud of, so why not? Again Patriosm is good, Jingoism not so much.