A small spark can cause a massive fire; metaphorically describes how a tiny force can grow into a powerful movement or how a minor issue can lead to a great disaster.

a wildfire spreading across a plain; a powerful, unstoppable force, often referring to a widespread uprising or revolution

to spread very rapidly across a wide area; used to describe a situation or trend that expands quickly and cannot be stopped

a single spark can start a huge blaze; an insignificant cause can have a massive effect or can develop into a powerful force; often used to describe small movements that grow to be unstoppable