Pretty much this, both sides know that a large surprise attack against the entire triad would be effective. That’s why monitoring of military exercises and oth

Pretty much this, both sides know that a large surprise attack against the entire triad would be effective. That’s why monitoring of military exercises and other precursors is critical. It’s very hard to kill all nuclear capable aircraft when they are already in the air. Placing all submarines on an alert posture also helps prevent the possibility that they’ve been intercepted. An around the clock war room helps ensure the president makes the decision to launch.