IN no Indo-US dialogue in the past half century have the participants been as tightlipped as in the three rounds of talks that US deputy secretary of state Strobe Talbott has had with the prime minister's special envoy, Jaswant Singh. Despite this, as the talks have progressed, more and more of the details have seeped out. This is itself a good sign, for it shows that the two sides found more and more common ground and have begun, by degrees, to relax. In his carefully measured statement to Parliament on August 4, the PM as good as confirmed that on one key element in the discussion India and the US had virtually come to an agreement: barring some unforeseen hitch, India is likely to sign the CTBT in the not-too-distant future.