"The shot that was heard around the world" refers to the opening conflict of the American Revolutionary War during the battles of Lexington and Concord on April 19, 1775. This phrase encapsulates the idea that the events occurring in the American colonies would resonate globally, inspiring other nations and colonized peoples to pursue freedom and self-determination. The confrontation represents a pivotal moment in the fight against British imperial rule, demonstrating the colonies' unity and resolve. This initial clash sparked a war that ultimately led to American independence and significant changes in political thought worldwide regarding democracy and governance.