(CNN) -- Just moments after Mitt Romney triumphantly introduced Congressman Paul Ryan to American voters on the deck of the battleship USS Wisconsin, I happened to witness a heart-wrenching event on the tarmac of an airport hundreds of miles away: The casket of a fallen service member was returning home to his family in Florida. As I stood silently with a group of passengers watching a small honor guard march to attention, the hearse backing up to the conveyor belt, and the grieving family members holding each other up, I was reminded again that a nation's foreign policy has direct impact on all our lives.
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Frida Ghitis: Presidents face unexpected challenges when it comes to international affairs
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Ghitis: It's hard to find a sharp difference between Romney and Obama in foreign policy
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She says Obama and Romney disagree about the future Pentagon budget
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Ghitis: Obama or Romney will likely preside over conflict with Iran and involvement with Syria
Despite vague criticisms, Romney is on record supporting Obama's plan to remove @placeholder forces.