Word credibility can be defined as the believability of words.
156,000 Alied troops took part in the D-Day invasion.
National security policy is a balancing act between Military force and Diplomacy.
Military forces are needed when a direct threat exist and we need to take care of it immediately to protect our people from hurting.
Meanwhile, diplomacy is the acts to maintain peace with another group/country and prevent the threat from happening in the first place.