Second this. A phone number is tied to an individual. Even though the conversation is secure,it makes targeting easier since the attackers know who is talking t

Second this. A phone number is tied to an individual. Even though the conversation is secure,it makes targeting easier since the attackers know who is talking to whom(comments on pgp usage and why the NSA loves pgp: https://www.theregister.co.uk/2016/01/27/nsa_loves_it_when_you_use_pgp/ https://www.theregister.co.uk/2016/01/27/nsa_loves_it_when_y... ,former NSA chief hayden also made similar remarks). Let'a say a journalist is targeted by a sophisticated attacker. The attackers want everything on the phone,why just calls and messaging? They won't even attack the protocol,they'll first try putting a RAT in place which will have access to everything. Signal does not promise to protect your communication after your phone is compromised(which only makes sense) but now the attackers don't just have access to your messages but also to your contacts. They now know the journalists sources and contacts by the phone number they used.