That interpretation is inconsistent with the founders' own statements on the subject. They were very clear in their opposition to a standing army. But in any case, the weapons cache at Concord was assembled voluntarily. Nobody was robbed to pay for it, and nobody was forced either to contribute to it or to defend it. In other words, it's a perfectly good example of voluntary defense. It's not a good argument in favor of compulsory taxation or conscription for defense.
I'm sure your historical studies will also have reminded you that the Minute Men were so-named because they were training as an organized military body...
Where did you get the idea that I'm against training? I'm all for it! What I'm against is theft, slavery and other forms of coercion.
You started off by implying that a disorganized force was not only as good as, but actually better than the trained British military. As it happens, the voluntary forces were badly defeated both at Lexington and Concorde, and the Continental Army was recognized at the time to be sorely inferior to the British troops.
They were very clear in their opposition to a standing army.
And they had valid reasons for saying so. But they were also not fools -- which is why they ended up creating a standing army very soon after independence. See here for an excellent discussion of the matter.