By 2019, servicing of national debt will be equal to one new TARP per year

With the national debt now topping $12 trillion, the White House estimates that the government’s tab for servicing the debt will exceed $700 billion a year in 2019, up from $202 billion this year, even if annual budget deficits shrink drastically. Other forecasters say the figure could be much higher.

In concrete terms, an additional $500 billion a year in interest expense would total more than the combined federal budgets this year for education, energy, homeland security and the wars in Iraq and Afghanistan…

Even a small increase in interest rates has a big impact. An increase of one percentage point in the Treasury’s average cost of borrowing would cost American taxpayers an extra $80 billion this year — about equal to the combined budgets of the Department of Energy and the Department of Education…

The White House estimates that the government will have to borrow about $3.5 trillion more over the next three years. On top of that, the Treasury has to refinance, or roll over, a huge amount of short-term debt that was issued during the financial crisis. Treasury officials estimate that about 36 percent of the government’s marketable debt — about $1.6 trillion — is coming due in the months ahead.