The closest you will ever get is the HTC Merge from Verizon. It has the 3G 2100 support. I suppose it may have 2G GSM support too but its not clear if it does. The 2100 band would cover all of Europe, Asia and in between anyway. But won't do any good in Latin America and Australia where the 3G is like AT&T's band at 850.
Of course there is also the Droid 2 Global, but its an HTC forum here, not Motorola.
The other problem is that the HTC Merge, and like every other CDMA phone you will get, are all locked. The Merge and the Droid 2 Global does have a GSM SIM slot, but you can only use it with Vodafone SIMs however. With Vodafone owning 48% of Verizon, I guess that's the reason for it. This sordid practice goes back to Blackberries such as the "World Edition", the Storm and the 9630 Tour.
But if you're with AllTel, Sprint, and US Cellular, tough luck, they simply don't have CDMA global phones. Only CDMA roaming arrangements that will cost you an arm and a leg. As a note, CDMA can directly roam in some countries that do have CDMA like India, China, Indonesia, Korea and Japan.
But let's be blunt. It's just better for you to go to a tech mall in Asia, pick up that unlocked HTC Legend, Wildfire, Desire (Z/HD or just Desire), buy a prepaid data SIM, preferably those that support 3G Huawei or ZTE modems which are what everyone uses these days, and stick that SIM into the phone. Then enter your Google account login and off you go.
If I were living in the US, I would stick to T-Mobile, since all the Android smartphones there have an optional 2100 band 1 frequency, not just the 1700 AWS frequency. They do it because T-Mobile happens to be owned by Deutsch Telecom, aka T-Mobile in Europe. Get the phone unlocked, which may break your warranty, but that phone will at least be 3G in both US, Asia and Europe.
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