This despite asking the dean what day it was.
Following in the footsteps of former US Presidents Richard Nixon, Bill Clinton and George W Bush, Obama laid a wreath at the tomb of the Unknown Soldier and went in to the nave to sign a heartfelt message in the Distinguished Visitors' Book.
The US President, after checking out the date with Dr John Hall, the Dean of Westminster, wrote, "It is a great privilege to commemorate our common heritage and our common sacrifice."
At first appearance one might take it as a deliberate action on the part of Obama to commemorate a historically significant day for him. It was May 24, 2008 when he accepted Hillary Clinton's apology for saying that she was staying in contention because of her memory of Robert Kennedy's assassination.
Though he went on to lose that primary, his popularity soared up and he went on to become the first man of colour to become the President of the United States.
Now he eyes another stint as the US President and his ratings are on a downslide after failing to uplift the American economy from the quagmire of recession. While trying to put on the same date that marked his upward rise, he might just be hoping that fortune favours him to get a second term as the President of the US.
On the other hand, this might be just another of his many gaffes. His history of appearing stupid dates back to the day when he was sworn in as the President. He made a mistake in his oath and had to be sworn in a second time to make him the legal president.
In 2009, he referred to his bowling skills as "like the special Olympics or something."
Whatever the reason may be for the guffaw, it was certainly not befitting a person of Obama's stature.