He indicated that he thinks of himself "not just" as a U.S. citizen, but as a "citizen of the world."
As a child, "I learned a lot about the dislocations, the packing up, the moving, saying goodbye to friends, meeting new friends, being in a foreign country," Kerry told the U.S. Embassy-London staff on Monday.
"And that experience, I’ll tell you, truly, is one that just lasts with you forever. I think back on the – such sense of independence that I gained and the confidence about meeting people in another country, seeing another culture, learning another language, and seeing the rest of the world.
"And in the end, we are not just – though we are proudly citizens of the United States of America, we are also citizens of the world."
Kerry told the Embassy staff that foreign policy nowadays is "much tougher" than it used to be -- because "all those forces that got tampered down by totalitarianism during the 20th century have all been unleashed. And now you see the sectarianism, the tribalism, and nationalism and these individual aspirations, and it’s tougher with a lot of young people all communicating to each other through the internet and social media, all having these big aspirations and leaders that are fighting against modernity. That’s what’s going on."
Kerry told embassy employees the U.S. is making a difference around the world. He cited the fight against AIDS in Africa, help for earthquake victims in Haiti, and the war on drugs.