had no rights? Don't say George the Third because he was a constitutional monarch governed by Parliament who had no power, and don't say Lord North because he was merely head of a government of ministers, also not a singular entity.
Your learning, while extensive, has not taught you to parse the argument properly. There was no Tyrant, singular, there was a Parliamentary tyrrany of the Old World politicians over the New based mostly on economic reasons. Read a good history of the causes of the Revolution which discusses the economic basis of the revolt and the Colonists desire to avert taxation on any goods imported, in other words smuggling. If you visit Boston, smugglers' tunnels are on the Historic Tour.
From your post: "Note that "Their swords and every other terrible implement of the
soldier, are the birthright of an American ." indicate that the founders
were aware of new technology in weapons and expected the citizens to be
able to arm themselves equally as well as any domestic or foreign
soldier whether friend or enemy." Emphasis RTB.
It indicates nothing of the sort. The "other terrible implement"s available at the time were scythes and bill hooks and any other object that could be turned into a weapon, and nobody wanted to go into battle with a bill-hook against a musket. The first broadly organized industry in the rebellious Colonies was the arms industry at Springfield to supply the Continental Army, thus contradicting the assertion of Tench Coxe before he even made it (the Army had the single largest stock of weapons available anywhere by the end of the Revolution, safely stored in armouries).
And as a man of your learning should know, there was very little in the way of innovation in the development of firearms between the end of the 17th and the beginning of the 19th Centuries. The Brown Bess musket was mildly improved by rifling, but the Baker Rifle wasn't invented for another 20 years or so, and it wasn't a rapid fire weapon either. It wasn't until the Post WW2 era that rapid fire accurate small arms began to pose a real threat to people in general (outside of the Elliot Ness tv show) and not until the 1970's that they began to show up on the streets, 200 years after the founding of The US. The Founding Fathers would have needed an amazing crystal ball.
As to mass shootings. Remember Charles Whitman shooting 15 people in and around the University of Texas in 1966, with an M1, a semi auto 12 ga, and other weapons both hand guns and bolt action rifles? HIs behaviour appears to be the first of the suicide by mass murder events at least in my understanding.
The amount of stupidity talked around the Second Amendment is also a recent phenomenon. It was clearly understood until the mid to late 60's that the most important words were in order for there to be a well-regulated Militia citizens shall have the right to keep and bear arms. The right wasn't predicated on the Militia, but the right was there to facilitate the rapid availability of the Militia. It was a right born out of the fear of government turning into tyrrany. The Militia wasn't to fight the British or any other foreign army, it was to prevent one or other of the States from becoming a dictatorship, or going haring off into contradictory interpretations of American Law and the Constitution as occurred in 1861. And even then the Secession was not put down by a self-armed militia, but by a centrally armed Army. The South was the side which tended to be armed with less professional quality arms.
I am tempted to ask: Had an Atomic Bomb or some equally expensive piece of technology
been available to the British, do you think that the Founding Fathers
would have advocated a Nuke in every Settler's house??
There is no evidence that "several thousand of these same (gun) owners did prevent criminals from doing such things." There may be a few dozen incidents per year, maybe a bit more, but gun advocates always inflate the efficacy of weapons' possession as a deterrent, just as they refuse to acknowledge the toll of accidental deaths, suicides and homicides which would not have occurred had the weapon not been present.
In Maryland, in the 50's, I was taught to lock up the guns and the ammunition (we had quite a number) and keep a baseball bat behind the door. I still do. I was also taught to walk facing traffic when there was no sidewalk, and to be aware of what was going on around me, and not to walk down dark alleys. It's worked so far.
Rob