The US has found evidence that Pakistan-based Lashkar-e-Toiba (LeT) has links with Osama bin Ladens al-Qaeda,and that operatives have trained in common camps,with cadres crossing over and cooperating in pursuit of their terror objectives. In an interview with The Indian Express,counter-terror expert and George W Bushs Secretary of Homeland Security Michael Chertoff revealed that jehadi groups like the LeT are not free-standing but operate in a web directed by a common ideology. During my tenure as Homeland Security Secretary,I have come across evidence that Lashkar terrorists had trained with al-Qaeda operatives. To believe that terror groups operate independently is an untenable view, he said. While Chertoff said that Washington did not have any prior inkling of 26/11 in the context of David Coleman Headley,he said that a Homeland Security and US intelligence team had visited India after the Mumbai attack to study the tactics of the Lashkar terrorists and make requisite changes in American counter-terror strategy. The Mumbai attack demonstrated a change in tactics on part of the terrorists targeting India. From single to multiple bomb blasts,26/11 was a combination of firearms and bombs,a kind of rolling attack, he said. India should be looking towards a layered defence against terror attacks and with an effective plan to respond in the wake of such a strike,said Chertoff,who has now set up high-profile security consultant group that has former CIA head Michael Hayden on its board. He said that India is in a dangerous neighbourhood with terrorist safe havens such as Afghanistan and Pakistan in the vicinity. In this context,he said that the Indian collection,fusion and analysis of intelligence should be designed for optimal response as there would be little lead time in the event of terror attack. The Indian Ocean is no longer a protective device but a cause of maritime concern with 26/11 being the latest example, he said.