Errrr, no.

Well, not from a HW point of view at least; you're talking about a totally different RF hardware team (nothing is common, pretty much) then different baseband software stack, maybe different software interface to the applications processor, a new RF test team (different specs, different standards), a new approvals team to deal with the approvals, then every test you run on the hardware from reliability to EMC to ESD has to be run on two different designs.

If you look at eg, how motorola is structured, they have totally different teams working on CDMA and GSM variants of their phones. It's not like one team cranks out both; a platform team will make the AP section then two separate RF platform teams will contribute the RF platforms, then two separate project teams will glue bits together and deal with all the integration issues.

Can it be done? Obviously it can be done. Motorola and HTC do it all the time. Ever noticed how Apple tends to concentrate their effort on one thing at a time and do it really well instead of trying to please everyone?

Look at it in that context and you'll see why if you're picking one thing to make, you don't make a CDMA phone. It's needlessly limiting. Make a WCDMA/GSM phone and you can sell it everywhere including the USA.