Y’all are right that the differing bang for the buck among nations makes a one to one comparison often skewed. On the other hand, we are blessed in this country in that we do not have to have to bear the expense of a large standing army to defend the homeland against neighboring armies, just a more serious effort to police the borders.
It might be mentioned that China’s entire defense budget is paid for the by USA, with interest payments on that part of our debt that China holds.