You started the thread showing a two criptic links comparing EU Debt and U.S. Debt and and appearing to show that U.S. had more debt. You did not make any comment beyond posting the links for comparison of debt to GDP.
My questions of you and my comment were designed to focus the issue on growth in the future. My point is that the amount of debt can only be considered excessive if you expect future growth to be lower than the cost of the accumulated debt. If you accept that you should see that the issue is about the comparable expectation of future growth and not the amount of accrued debt.
I reject the idea that government spending contributes to growth...government spending is of course spending and can only be considered 'investing' in the most cynical rhetorical sense. As spending, government spending, reduces investment that creates real growth. Government spending, like consumer spending, can only occur if it is funded by past production surplus ('savings'), current production surplus ('profits'), or future production surplus ('debt'). All spending is dependent on production in the past, present or in the future. All income to pay debt is dependent on production in the future. Production in the future is highly dependent on investment in production presently and historically. Where policy diverts savings, profits and debts to consumption then future production will decline and debts will become unsustainable.
Can you see that the idea of excess debt has everything to do with your view of future production...call it growth, income, wealth, or the increase in 'assets.' In a classical sense you become insolvent when the cost of your debt begins to exceed the income from your assets. The whole idea of investment is to create or maintain assets.
I return to the question...who has the best possibility of maintaining and increasing thier base of aggregate assets such that the income from those assets can carry and reduce the debt?
I reject GDP as a proper measure of growth...It is a measure of spending, not growth.