Interest. Or to be more precise, interest payments. That, Heritage Senior Fellow J.D. Foster ^[1] explains, is the biggest reason why Americans should be very concerned with the trillions of dollars in debt our federal government is piling up in Washington. Watch:

And the situation is only going to get worse under President Barack Obama’s budget. Heritage Foundation fellow Brian Riedl reports ^[2]:

Federal spending (which has remained around 20 percent of economy since the 1950s) would surpass 28 percent of economy by 2019. Federal spending per household would rise from $25,000 per household in 2008 to more than $37,000 per household by 2019.

This spending would drive a permanent, unprecedented increase in the national debt. After borrowing just under $6 trillion from 1789 through 2008 (plus nearly $2 trillion in 2009), Washington would borrow $13 trillion over the next decade–nearly $100,000 for every household. By 2019, annual budget deficits would approach $2 trillion and push the public debt to nearly 100 percent of the economy. Merely paying the interest on this debt would soon cost taxpayers $1 trillion annually, and spending and deficits would continue to rise.

^[3]

For more charts see Heritage’s National Debt Charts Facebook photo album ^[4].