The question, as I see Barack framing it, is, "Does the U.S. Constitution apply to those outside the United States?" If, as Sen. Obama implies, it does, then he needs to call out all countries that deny rights guaranteed by OUR Constitution to their citizens. Is he willing to take on muslim countries that deny freedom of religion? or press? I think not. What about muslim counties that treat women as second or third class citizens? Sen. Obama's silence is deafening. Is he willing to call out Don't bet on it.
IMHO, Constitutional protections stop at our border. They cannot (and should not) be extended to the citizens other contries via caveat. Otherwise, the U.S. is faced with declaring war on every country that does not honor the God given rights enumerated in the Untied States Constitution.
Is he willing to call out allies that deny citizens the right to keep and bear arms? Probably not.