Short Answer 
The scene depicts Capulet’s ineffectiveness in conflict, as he is humorously advised to rely on a crutch due to his age, while Montague merely pretends to engage by waving his sword without intent to fight. This illustrates that both leaders symbolize the futility of their feud, escalating tensions without genuinely participating in the violence.
Step 1: Capulet’s Ineffectiveness
In the scene, Capulet attempts to participate by calling for a sword, but Lady Capulet humorously suggests he should instead use a crutch. This illustrates Capulet’s age and inability to engage effectively in a physical confrontational situation. The comedic contrast emphasizes his frailty in comparison to younger fighters.
Step 2: Montague’s Posturing
Capulet mentions Montague “flourishing his blade in spite,” indicating that Montague also does not join the fray. Instead, he is merely waving his sword around without real intent to fight. This behavior reflects a certain mockery of the situation, as it shows that neither of the heads of the feuding families are genuinely involved in the conflict.
Step 3: Symbolism of Leadership
The actions of both Capulet and Montague symbolize how the leaders of their respective houses are not effective in stopping the violence. Instead, they contribute to the escalation of conflict without being on the front lines. This highlights a cycle of futile aggression that persists despite their actual ineffectiveness in combat.