Come back and tell me when you understand some history of Ireland as a whole, the Six Counties in particular, the conflict between Nationalists and Unionists, how this played out across the island of Ireland and over into, especially, England, how sectarianism in parts of Scotland is directly linked to the situation in the Six Counties...There are a few folk here who can tell you a lot more than I can and there is a very extensive literature.
And you might be starting to get a hint of an inkling that flags don't exist in a vacuum, that they have long been used in very specific ways, to provoke specific responses, to incite deadly violence, that their use comes with a lot of baggage and that this (as with many other things) does not fit with your naively simplistic USA-centric view of how the world and societies work.
Which is definitely ironic since one of the things the Mayflower mob wanted wass freedom to oppress those of differing religious beliefs...