US Defence Secretary Ashton Carter has said, India-US military relationship is the closest it has been ever and the two countries are exercising together by air, land and sea for the first time. <br/><br/>In his remarks aboard the USS Carl Vinson in San Diego, he said the two great democracies have done a strategic and technological handshake. Carter said the US-India Defence Technology and Trade Initiative grasps hands with Prime Minister Narendra Modi's Make in India campaign, helping both countries move toward more diverse defence co-development and co-production of weapons systems.