Here is the full text of the Second Amendment in the US Constitution, which governs all laws in the US...
A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed.
The right of self defense is not in dispute. Never has been throughout history. So self defense was not a component in the debates -- plural -- prior to the enactment of the Second Amendment into the Constitution.
On the other other hand, the idea of the citizenry having a say in how they are governed have always been in dispute and the worst type of dispute of all is -- violence.
Let us take what Mao said about political power...
https://www.marxists.org/reference/archive/mao/works/red-book/ch05.htm
Every Communist must grasp the truth; "Political power grows out of the barrel of a gun."
Now let us take what von Clausewitz said about warfare...
https://www.clausewitz.com/readings/OnWar1873/BK1ch01.html#a
24.—War is a mere continuation of policy by other means.
We see, therefore, that war is not merely a political act, but also a real political instrument, a continuation of political commerce, a carrying out of the same by other means.
What this means is that the relationship between state and citizenry is
ONLY political in nature. Nothing else matters. Violence is a tool or a mean to assist in the finalization of a political goal.
The Second Amendment is essentially a political statement. Other countries have allowances for personal possession of weapons, but the US's Second Amendment is unique for over 200 yrs in that weapons are tacitly declared as political instruments reserved without restraints to the citizenry as a final -- and violently if necessary -- check against the state.
The words 'regulated Militia' does not mean the National Guards or police forces. A militia is an organically created organization, often spontaneously, when the citizenry felt, rightly or wrongly, the need for one. A militia is a citizen's, not the state's, armed forces. So if there is to be a militia, the citizens themselves must be allowed to be armed however each person is capable.
The vast majority of American gun owners are responsible and knowledgeable on what I said above regarding the political aspects of the Second Amendment. You can cherry picked instances of when a person should be allowed to own guns, but that does not take away the political aspects of the right to own guns.
At the intellectual level, threads like this one are essentially troll threads. The posts are from people who made no efforts at 'root cause' analyses or even general understanding of why guns are allowed in America. The 'root cause' here is the Second Amendment, not mental health or drugs or money.