If you spend 8% and the GDP is boosted by 4% once, and then grows at the normal rate afterwards, then the GDP will stay 4% larger indefinitely. That 8% debt wo

If you spend 8% and the GDP is boosted by 4% once, and then grows at the normal rate afterwards, then the GDP will stay 4% larger indefinitely. That 8% debt would generate 4% more economic output this year, next year, the year after, the year after that, etc... If your 8% debt only generates 0.5% of extra growth once, and then we get back to a baseline 3.5% growth, the additional economic output will equal the debt in 16 years and continue generating economic output afterwards. But it's also completely unclear why, as a government, you should care about the ratio of debt to growth. The two numbers are of an entirely different nature. That economic output corresponds to things produced by the economy. The 8% debt corresponds only to who has control of which money pile (in particular, it includes the promise that the government will redirect a large chunk of money to the lenders in the future, which you might or might not find problematic). It doesn't take anything away from the total sum. So by shuffling money around, you have created real economic output. That's great!