(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
Obama
Obama
Obama
Despite vague criticisms, Romney is on record supporting @placeholder's plan to remove American forces.
American
Despite vague criticisms, Romney is on record supporting Obama's plan to remove @placeholder forces.
Mitt Romney
Romney
Romney
Romney
And if you look closely at @placeholder's proposals for Iran, what he calls for is more economic sanctions.
Paul Ryan
Romney and @placeholder, if they win, are likely to up American involvement in the Syrian conflict, and they may well preside over an American conflict with Iran.
American
Romney and Ryan, if they win, are likely to up American involvement in the Syrian conflict, and they may well preside over an @placeholder conflict with Iran.