According to the nonpartisan Center on Budget and Policy Priorities (CBPP), the Bush-era tax breaks for the nation’s top earners, combined with the costs of fighting wars in Iraq and Afghanistan, will account for nearly half the public debt in 2019 when measured as a percentage of economic output.

As the chart below demonstrates, our national debt without the Bush-era tax breaks and spending on the wars in Iraq and Afghanistan (but including TARP, the economic downturn, and recovery measures to mitigate the effects of the downturn) would be just about 40% of the nation’s Gross Domestic Product (GDP). However, add in the Bush-era tax cuts and the wars in Iraq and Afghanistan and the national debt as a percentage of GDP jumps to nearly 90%.

[S]imply letting the Bush tax cuts expire on schedule (or paying for any portions that policymakers decide to extend) would stabilize the debt-to-GDP ratio for the next decade. While we’d have to do much more to keep the debt stable over the longer run, that would be a huge accomplishment.

According to the CBPP:

While there’s no denying that there’s probably no shortage of opportunities to cut/streamline spending by the federal government, if our elected officials (especially Republicans) were really serious about solving our nation’s debt problems, they’d start by letting the Bush-era tax cuts expire, instead of cynically using our nation’s debt problems to push to eliminate programs like Medicaid, Medicare, and Social Security, programs which have certainly served the common good for decades.