President Obama's cranes

President Obama's 4 cranes are now on display at the Hiroshima Peace Memorial Museum:

HIROSHIMA – The Hiroshima Peace Memorial Museum on Thursday put on display four paper cranes offered by U.S. President Barack Obama during his historic visit to the atomic-bombed city in May.
According to the museum, each of the Obama-handmade cranes is about 7 cm high and about 10 cm wide, and made of pink and blue paper with Japanese-style floral prints.
Obama visited the museum before attending an official service in the Peace Memorial Park on May 27. He gave one crane each to two local schoolchildren who welcomed him at the museum.
He also left another two when he signed the museum’s guest book with a message: “We have known the agony of war. Let us now find the courage, together, to spread peace, and pursue a world without nuclear weapons.”
Visitors have been taking photos of the paper cranes and message, which are on public display inside a glass case until Aug. 31.

Hat tip to Mark Kennedy, who also notes the number "4" is regarded as unlucky in Japanese superstition, due to the pronunciation of "4" also is the word for "death".

Someone advising President Obama missed the boat on that one.