President Asif Ali Zardari's trip to Britain was particularly ill-fated. When he first planned a visit which should have culminated in him bringing his son, Bilawal Bhutto Zardari, out into the political arena, no one could have predicted such a bewildering series of crises. A row with Britain over remarks made in India by British Prime Minister David Cameron that Pakistan must not "look both ways" in its approach to Islamist militants. Pakistan's worst floods in 80 years. A plane crash, and then riots in Karachi.