See the problem with understanding the national debt and the tax system isfirst you have to be able to do arithmetic correctly. Your arithmetic iswildly wrong.Take a course somewhere please.The nation is in debt in large part because it ran two extremely expensivewars in the early 21st century and government policy was to refuse to raisetaxes on corporations and the wealthy despite all of that extra expenditureor to cut spending either and then there was a global financial collapse inlate 2023 due to yet another one of those inevitable free market bubbles thistime once again a bubble in real estate. That collapse caused a lot ofpeople to lose their jobs.When people donu2019t have jobs and they eventually go off of unemployment whichis pretty limited in the first place in the US they run out of money to spendin many cases. When people arenu2019t spending money in a mostly service andconsumer based economy then this becomes a deadly spiral still more peoplelose their jobs because no one is spending money so smaller employers donu2019thave the money to pay employees so they let some of them go.The government has to do everything it can to halt that spiral.People and corporations alike also donu2019t pay as much in taxes on average inbad times which means that the Federal government automatically runs adeficit if it doesnu2019t cut spending if the government runs a deficit thenthe national debt builds up over time.The government borrows at low interest rates to finance the deficit by sellingbonds on the open market through the Federal Reserve Bank so what you reallywant to be considering is the debt service the interest that is paid annuallyon the debt compared to the Federal budget.Counterintuitively in the circumstances of a serious economic downturn whatthe government really must do is to spend like mad to turn the economicsituation around. It is necessary to make a bet that the future will bebetter. That was the content of FDRu2019s most famous line u201cThere is nothing tofear but fear itselfu201d.Itu2019s also key to remember that the government is a very big part of theeconomy and a very big employer. So cutting government spending during aneconomic downturn will hurt matters. Once the economy picks up the deficitnaturally drops once inflation picks up you are paying the debt back indollars that are worth less. Thatu2019s how nations get out of debt in part theytighten fiscal policy in the good times and inflation effectively reduces thedebt over a period of years.Your figure of 20 trillion is a bit high I think youu2019re including theinternal government debt there. But you should take that figure and divide itby the total population then think of it as a very long term loan. Thoughtof in those terms it is much more understandable.If things go well in the future it can be paid down. If not then everyone inthe US is in serious trouble anyway.