The growing debt will burden Americans not just with heavier taxes but also with higher interest rates and slower economic growth. On June 3, Fed chairman Ben Bernanke warned Congress that heavy borrowing is one of the factors driving up rates. The trend is just beginning, according to Allan Meltzer, the distinguished monetarist at Carnegie Mellon. “Rates can only stay low if foreign investors keep buying our debt,” he warns. “I predict far higher rates over the next few years.” The risk that the U.S. will follow Britain, which was warned recently that it could lose its triple-A bond rating, has risen from virtually nil to a real possibility, judging by the sevenfold jump in the cost of insuring Treasury debt in the past year. The big borrowing is already spooking the bond markets. This year rates on 10-year Treasuries have jumped from 2.2% to 3.7%. A further increase in rates would aggravate the situation, raising the interest costs on the debt and increasing its size even more…

It can’t go on forever, and it won’t. What will shock America into action is the prospect of fiscal collapse, which will grow more vivid each year. In 2008 federal borrowing accounted for 41% of GDP, about the postwar average. By 2019 the burden will double to 82% by the CBO’s reckoning, reaching $17.3 trillion, nearly triple last year’s level. By that point $1 of every six the U.S. spends will go to interest, compared with one in 12 last year. The U.S. trajectory points to the area that medieval maps labeled “Here Lie Dragons.” After 2019 the debt rises with no ceiling in sight, according to all major forecasts, driven by the growth of interest and entitlements. The Government Accountability Office estimates that if current policies continue, interest will absorb 30% of all revenues by 2040 and entitlements will consume the rest, leaving nothing for defense, education, or veterans’ benefits.

To understand why a massive tax increase, probably a VAT, is the mostly likely outcome, it’s crucial to look at what’s driving the long-term, widening gap between revenues and spending…

[Paul] Ryan despises the VAT as the beginning of the end of the American empire. “The VAT is definitely the trajectory Obama is putting us on,” he laments. Ryan believes that the big growth in government in Europe came from the easy money it provided. He makes a good point. It’s not a destiny to be desired. And when the two Pauls agree, you can bet it’s where things are headed.