"A fact of life NOT shared by say, the neighbors of Belarus or Russia or China."
And that is the point Scotland is NOT a neighbor of any country that is likely to pose any threat.
It's hard to see Russia invading just Scotland for example. And any problems with fishing aren't going to end in a war that requires a large military presence. No, they can just not have any armed forces knowing that the rest of Europe is in the way of any serious possible aggressor. Ireland did that in 39-45. A lot of Irishmen joined up and fought for the British for various reasons and I'm sure there'd still e be a steady flow of Scots in the ununited UK Armed forces but the Scottish Govt know they don't have to bother...