House Minority Whip Steny Hoyer made this argument in broad strokes on Monday. Hard numbers back it up.
The Center on Budget and Policy Priorities has updated and refined a widely cited chart, laying out the origins of the country's current fiscal trajectory. And as before, the lion's share of the problem comes from ongoing George W. Bush-era policies -- particularly deficit-financed tax cuts, which eliminated Clinton-era surpluses and left the Treasury poised for a huge hit when the financial crisis and economic downturn further eroded federal revenues.
By the end of the decade, CBPP projects that, on the current trajectory, the Bush tax cuts, exacerbated by the economic downturn, combined with the wars in Iraq and Afghanistan will account for the significant majority of public debt as a share of GDP.
Without those factors, and without the need for stimulus measures under President Obama, CBPP projects that the debt-to-GDP ratio would have dropped under both Presidents Bush and Obama.