Disclaimer: I'm European. I have never been in the U.S. I am not related to Nokia at all.
Reading Hacker news and other U.S-centric news sites, it looks like there is nothing but Apple and Android. Whenever Nokia gets mentioned, there is some disdain. However, Nokia sells about 35% of all mobile devices in the world. I myself own one. I really like the platform. It is open source, it runs Java, it supports Flash and it is very pleasant to write applications using C++ and QT. It is a no-BS platform, just unlike Apple's policy-hell. In short, from my point of view is the ideal platform to build for: huge market, no politics, solid open source platform.
Why is it almost always ignored? Did they do something horribly wrong in the U.S. market and never recovered? Is it seen as "unpatriotic" because is foreign? Do you feel it as technically inferior?
That's Nokia's problem as well. The cell-phone market in the US is much different from Europe and the rest of the world. It is my understanding that in Europe and the rest of the world people by phones (usually in cash) and service separately (often prepaid), so cell phone makers have only one customer to please: the end user.
In the US, where we are addicted to credit, people buy phones primarily through the cell phone provider for a big discount in exchange for signing a 1 or 2 year contract. Since the selection of phones drives the profit for the cell phone provider (See AT&T and the iPhone for an example), the phone company has a huge stake in making sure the phones fit their image. So the cell phone maker has 2 customers - the phone company and the end user. Every carrier has a signature phone: AT&T - iPhone, Verizon - Droid, Sprint - EVO 4G. These phones become almost synonymous with the carrier, and less with the brand (iPhone being the big exception).
Nokia's problem for the last decade is that they have been used to pleasing only the end user, that they have not been able to win over the American cell phone providers. A good example is the late 90's, where Americans had moved on to flip phones, but Nokia was still pushing brick/candy bar phones. They are starting to innovate, but they still haven't captured the heart of the American cell phone buyer.
The other hurdle for Nokia is CDMA. I'm not sure if they have CDMA versions of their phones (this is probably because they'd have to work with Sprint and Verizon to do so). They'd have to retool most of their phones to work in the US, which might not be worth it if the cell phone companies aren't on board.