It was a rare sight to have four of Japan's political heavyweights sharing a laugh during a get-together, reportedly on Aug 15. Prime Minister Shinzo Abe (second from right) and his predecessors (from left) Junichiro Koizumi, Yoshiro Mori and Taro Aso, a former prime minister who is now deputy premier and finance minister, spent a short vacation at a cottage at the foot of Mount Fuji at the invitation of Mr Yohei Sasakawa, chairman of the Nippon Foundation. The cottage belongs to Mr Sasakawa, who posted the picture on his blog. Japan Times said that as Mr Abe grapples with mounting challenges both at home and abroad, it has become increasingly uncommon to see him crack a smile in public. In a blog post last Wednesday, Mr Sasakawa wrote: "For Prime Minister Abe, playing golf is the best way to kill stress... I've heard he hasn't been able to play this summer because he had to... deal with issues of North Korea."