What is the combat ratio typically used for Area Defense?

In the context of military strategy, particularly regarding area defense, a combat ratio of 1/5 is commonly employed. This means that for every defender, there are five attackers. Utilizing this ratio allows defenders to effectively allocate their resources and forces against a larger attacking force, optimizing their defensive posture and increasing the likelihood of sustaining and conducting operations until reinforcements can arrive or until a strategic withdrawal can be executed.

The rationale behind the 1/5 ratio lies in the principles of attrition and maximizing defensive effectiveness. Defenders can use terrain to their advantage, employing fortifications and strong points to inflict greater damage on attackers despite being numerically inferior. This ratio has been proven effective in historical conflicts where defenders successfully held positions while utilizing obstacles and understanding the terrain.

On the other hand, the other ratios presented are not typically standard for area defense. A combat ratio of 1/2 or 1/3 would suggest a more favorable condition for defenders, which doesn't align with the necessity of preparing for a significantly larger and attacking force in an area defense scenario. Meanwhile, a 2/5 ratio might indicate a relatively balanced situation, which would not be appropriate for the principles guiding a robust defensive operation where a higher level of enemy engagement is anticipated