The nuclear deal between Iran and six major powers— P5+1— is like a feeble baby delivered after an unusually long labour, with the parents holding breath to see if the newly arrived can survive the crucial early months. Though the official birthdate was 24 November 2013, the deal came to life on 20 January, when Tehran stopped enriching uranium beyond 5 percent. US President Barack Obama, the lead midwife, has put the chance of the baby’s survival at no more than 50:50. Such caution is warranted.