What caused the national debt? 6 culprits - The Week 1. The Bush tax cuts The biggest culprit? The 2001 and 2003 tax cuts under then-president George W. Bush, says the Associated Press. They have added an estimated $1.6 trillion to the national debt. It's pretty clear, says Brian Beutler at Talking Points Memo, that Bush-era policies, "particularly debt-financed tax cuts," make up "the lion's share of the problem." And they're ongoing, so the tab for them builds every year. 2. Health care entitlements Democrats "constantly harp" about the Bush tax cuts, says Peter Morici at Seeking Alpha, but those rates were in place in 2007, and the deficit that year was one-tenth this year's budget shortfall of $1.6 trillion. So what has changed since then? Added "federal regulation, bureaucracy, and new Medicaid and other entitlements have pushed up federal spending by $1.1 trillion — $900 billion more than required by inflation." And down the road, says Yuval Levin at National Review, our "health-entitlement explosion" will account for "basically 100 percent" of our debt problem. 3. Medicare prescription drug benefit Another piece of the pie: George W. Bush's addition of Medicare's prescription drug benefit. That has added $300 billion to the debt, according to the AP. Expanding entitlements like Medicare, or last year's health-care reform package, is a particularly tempting way for Congress to run up debt, says Jagadeesh Gokhale at The Daily Caller. Since lawmakers don't typically map out a revenue strategy to fund those benefits, they are "shielded from the political costs of actually paying for the new programs." 4. The wars in Iraq and Afghanistan The tab for the wars in Iraq and Afghanistan comes to $1.3 trillion, another major chunk of new, unexpected spending over the last decade. "These wars cost us plenty," says Nake M. Kamrany at The Huffington Post, and they "have to be financed with borrowing, which adds up to national debt." 5. Obama's economic stimulus The 2009 stimulus package enacted by President Obama cost $800 billion. And the 2010 tax-cut compromise between Obama and Republicans, which extended jobless benefits and reduced payroll taxes, added another $400 billion to the debt. Add another $200 billion for the 2008 bailout of the financial industry, and the government's efforts to soften the blow of the Great Recession amount to one of the largest chunks of the debt build-up. The "federal budget was one good year away from balancing" after 2007, says Tom Blumer at News Busters. But in the years since, Obama and Democrats in Congress put that goal out of reach. 6. The Great Recession Some of the spending gap came from factors outside the control of Congress and the White House. As the government spent heavily to boost the economy, says the AP, it took in hundreds of billions less in tax revenue than expected, because the Great Recession eroded Americans' income and spending.