George W. Bush Angela Merkel Joe Biden Bill and Hillary Clinton Arnold Schwarzenegger Nicolas Sarkozy David Cameron Kathleen Sebelius and Nancy Pelosi Barack Obama and Joe Biden Gordon Brown Hamid Karzai Bill Clinton Dmitry Medvedev Dmitry Medvedev and Vladimir Vladimirovich Putin Michelle Obama and Bill Clinton Dmitry Medvedev and Silvio Berlusconi George H. W. Bush and Barbara Bush