I think you might be conflating a couple things, though in fairness you might just be bringing part of that argument over from others having been made. What I posted cited nothing regarding a deity not does it require the invoking of such to hold it's merit.
Setting aside the concerns of "natural law" the founders (as shown above, more detailed in Heller and elsewhere) were running with actual established law going back centuries. The codification in the 2A was to specifically preserve, not "invent" and grant some privilege. This stands on it's own. Now a very compelling argument could be made that the "natural" origin of the right is what I outlined at the beginning of my post...the concept of self-defense is intrinsic to life itself. (including animals and even plants Plant defense against herbivory - Wikipedia) And this also extends beyond individuals. Defense of home, community and State were all embedded in the 2A with actually the most overt aspect being the defense of freedom for "the people".
The Founders were coming out of literally use of arms to throw off the yokes of what had become viewed as a tyrannical government. They damned sure, by every means they could think of, wanted what came after was as insulated from becoming corrupt as they possibly could. Even knowing this at the time the founders were well aware that it is the nature of government to gather power unto itself and many in the governed to become complacent. Just one such quote from Jefferson:
They [the assembly] should look forward to a time, and that not a distant one, when a corruption in this, as in the country from which we derive our origin, will have seized the heads of government, and be spread by them through the body of the people; when they will purchase the voices of the people, and make them pay the price. Human nature is the same on every side of the Atlantic, and will be alike influenced by the same causes. The time to guard against corruption and tyranny, is before they shall have gotten hold of us. It is better to keep the wolf out of the fold, than to trust to drawing his teeth and talons after he shall have entered.
A disarmed population is one that lives at the largesse, or lack thereof, from it's government. There is no ambiguity of any sort that the founders were extremely aware of this fact.
“What country can preserve its liberties if their rulers are not warned from time to time that their people preserve the spirit of resistance. Let them take arms.” Thomas Jefferson
Many quotes of similar thought are to be found from the Framers.
To your last point it is, unfortunately, all too simple. For another TJ quote:
“I prefer dangerous freedom over peaceful slavery.”
Sadly, this is often not the case with many people, where even the illusion of safety is sufficient to cede freedoms. Worse, no shortage exist that are too weak to acknowledge they ever even had freedoms preferable to risk in the first place. There's a piece by Dostoevsky called the Grand Inquisitor that had a line in it regarding such people. It's chock full of quotes regarding freedom but two that really stuck with me are:
“Man is tormented by no greater anxiety than to find someone quickly to whom he can hand over that great gift of freedom with which the ill-fated creature is born.”
“In the end they will lay their freedom at our feet and say to us, Make us your slaves, but feed us.”
