descalada :
Remember this is just the manufacturing cost. This doesn't take into account the cost of developing the phone's hardware, software integration, and the countless testing cycles to get to the finished product. There is a lot of investment and overhead just to get to this point. Moto and all other handset manufacturers need to recoup the costs of this investment. Think of it like movies. The cost of a single DVD is 20 cents or less, but you pay $20 and receive a movie that may cost hundreds of millions of dollars to make.
Well, Steve Jobs said it in its time and made clear what the challenges were to bring back the "production" part to the US of A.
The first and more important part is workers willing to move in no time (overnight mostly) to keep manufacturing levels up to speed. And the technological part for facilities was the second issue he identified: they had factories ready for production in like 3 days, was it? China has been advancing in both points faster than the US of A, but it doesn't mean it will last forever. Besides, that's leaving the point of "21st century slavery" at bay.
In short, the "cost" itself doesn't reflect if these issues are solved/overcome or not, but if Motorola is willing to do so, I'm pretty sure more will join when more plants are built and can compete with China (or Malaysia) in price and productivity.
Cheers!