control the flow of information in order to protect operational integrity. the element of surprise. >> reporter: after american security forces leaked the identity of the manchester arena attacker. >> it's irritating if it gets released from other sources. i have been very clear with our friends that that should not happen again. >> reporter: but it isn't the first time. just two weeks ago sources reported donald trump shared information with russian aofficials in an oval office meeting. john brennan testified on tuesday that the president broke protocol in doing this. >> it appears as though from the press reports that neither did it go in the proper channels nor did the originating agency have the opportunity to clear language for it. so that is a problem. >> reporter: the fact it then became public knowledge was the bigger problem. >> that was where the damage came from. that it was released in the press. >> reporter: it was the president who appeared to