Britain, France, and the US are all nuclear power states that have armies equipped with the most modern weapons systems. Why are they still fighting the Taliban after 13 years? How is it that ISIS defies them?
Is it possible that there are factors that you aren't considering? It would seem so. Not even the apartheid state of South Africa which was a nuclear state for a period of time was ultimately willing to use nuclear weapons on its own people.
The dismissive statements that the two of you have made take no recognition of the facts of the matter. Do you think that the Swiss government could impose a tyranny on the Swiss? Hardly. Nearly the whole of the army is composed of reservists that keep arms at home. Israel? Once again, unlikely. The US? Unlikely, at least in a coup. Half of the total combat power of the US military is in the reserve forces composed largely of state militias. Much of the support is also in the reserves. To that you add the factor of the unformed militia which is legally defined as:
(a) The militia of the United States consists of all able-bodied males at least 17 years of age and, except as provided in section 313 of title 32, under 45 years of age who are, or who have made a declaration of intention to become, citizens of the United States and of female citizens of the United States who are members of the National Guard.
(b) The classes of the militia are—
(1) the organized militia, which consists of the National Guard and the Naval Militia; and
(2) the unorganized militia, which consists of the members of the militia who are not members of the National Guard or the Naval Militia.
So you see, those weapons are in the hands of the unformed militia which is responsible to defend the US Constitution again all enemies, foreign and domestic. That is a very useful addition to the state militias.
The case in many European countries is not as favorable. About 100 years ago in Britain free men and women owned large numbers of firearms, and bobbies pursuing criminals could appeal to the public for aid or arms. Those days are long gone, as is the mentality. The right of even self defense against attack has become endangered in Britain.
It appears to me that you aren't successfully identifying what is foolish, and there is plenty of that going on in Britain.