during the meeting with the five families and the other dons around the u.s, it was when vito was making his statement to tattaglia about foregoing vengance when tom sensed that something was "missing" from the puzzle. it was as if vito had something else up his sleeve but tom couldn't figure it out what it was and he couldn't bring himself up to ask. this missing piece of the puzzle that tom was sensing, was it vito planning the hit on barzini and tattaglia? or is it something else? (btw, i don't have the novel on me, so i apologise if the question seemed to vague)