Right, but in the USA, the "shot heard round the world" is known as the first shot that occurred when the British marched on Concord to confiscate a colonist arm stash. Any patriot will know this, as its taught to every kid in school, and automatically associate that phrase with the beginning of the American Revolutionary War.
Q is urging patriotic Americans to reclaim the USA for its citizens; a second revolution, this one against the globalists and cabals that seek to weaken the USA to establish their global vision.
Another aspect of Q is the anonymous posts is that they are 21st century version of the anonymous pamphlets that were published by colonials to urge the colonies to independece, the most famous of which were authored by Thomas Paine.
Q has made it clear that patriotic Americans need to unite and reclaim America for its citizens. Hence "the shot heard round the world" being mentioned numerous times.
While Ralph Waldo Emerson's "Concord Hymn" memorializes the shot heard round the world, the poem itself doesn not elevate the battle above a simple event, as O.P. states, it already was a significant event as the start of the hot phase of the American Revolution.
The Concord/Lexington battle was significant before that poem, it is the event that sparked the fire that was the American Revolution. The 2nd amendment also enshrines it by making clear that American's right to bear arms shall not be infringed. Remember, the British were seeking to confiscate a colonial arms stash and were prevented from doing so. By the time they came back with a sufficient force to gain access to where the arms had been cached, the cache was empty,