US President Barack Obama (Centre L) inspects the guard of honour 1st battalion Scots Guards with Britain’s Prince Philip (Centre R) at Buckingham Palace in London, on May 24, 2011. US President Barack Obama Tuesday basked in the lavish royal pageantry of a state visit to Britain, given an extra dash of glamour by a brief encounter with Prince William and his bride Catherine. AFP PHOTO/ ADRIAN DENNIS/WPA POOL (Photo credit should read ADRIAN DENNIS/AFP/Getty Images)