Handset producers and carriers are partners. They lobby and negotiate for each business dealings, and that's how Apple got their piece of the pie which most people don't think they deserve (a consumer product without any experience or known expertise in the cellular business). It was Steve Jobs' doing. He's a nutty snake oil salesman and a brilliant negotiator. He could bluff you to fold your pair of aces with his 7-2s (or whatever the worst hand in a holdem game is).

I don't know about Nokia's strategy in the US market, but so far it hasn't impressed anyone, even themselves. Please don't forget that these companies are businesses.. like living things needing to eat to sustain themselves, they focus on making money before any other things to sustain themselves...