Conservatives will tell you that Obama is to blame for the fact that the national debt is now passing $15 trillion dollars.  To be sure, Obama has added to the debt. 

But if you want to know how we got here, let's really look at the whole history of how we got here.

Steven Benen helps with the history:

1980: Ronald Reagan runs for president, promising a balanced budget

1981 – 1989: With support from congressional Republicans, Reagan runs enormous deficits, adds $2 trillion to the debt.

1993: Bill Clinton passes an economic plan that lowers deficit, gets zero votes from congressional Republicans.

1998: U.S. deficit disappears for the first time in three decades. The debt clock, which hadn’t been programmed to run backwards, is unplugged.

1999: The country begins paying down the national debt for the first time in more than three decades.

2000: George W. Bush runs for president, promising to maintain a balanced budget.

2001: CBO shows the United States is on track to pay off the entirety of its national debt within a decade.

2001 – 2009: With support from congressional Republicans, Bush runs enormous deficits, adds nearly $5 trillion to the debt.

2001 – 2009: Congressional Republicans throw caution to the wind, approving tax cuts, two wars, Medicare expansion, and a massive Wall Street bailout. They add every penny of the costs to the national debt.

2002: Dick Cheney declares, “Deficits don’t matter.”

January 2009: Barack Obama inherits $1.3 trillion deficit from Bush; Republicans immediately condemn Obama’s fiscal irresponsibility.

December 2009: Sen. Orrin Hatch (R-Utah) describes the previous eight years as an era in which Republicans believed “it was standard practice not to pay for things.”

2009 – 2010: Congressional Democrats unveil several domestic policy initiatives — health care reform, cap and trade, DREAM Act — which would lower the deficit. GOP opposes all of them.

September 2010: In Obama’s first fiscal year, the deficit shrinks by $122 billion. Republicans again condemn Obama’s fiscal irresponsibility.

October 2010: S&P endorses the nation’s AAA rating with a stable outlook, saying the United States looks to be in solid fiscal shape for the foreseeable future.

November 2010: Republicans win a U.S. House majority, citing the need for fiscal responsibility.

December 2010: Congressional Republicans demand extension of Bush tax cuts, refuse to consider paying for them, demand that the costs be added to the national debt.

March 2011: Congressional Republicans declare intention to hold full faith and credit of the United States hostage — a move without precedent in American history — until massive debt-reduction plan is approved.

July 2011: Obama offers Republicans a $4 trillion debt-reduction deal. GOP refuses.

August 2011: S&P downgrades U.S. debt, citing GOP refusal to consider new revenues. Republicans rejoice and blame Obama for fiscal irresponsibility.

October 2011: Working through the so-called super-committee, congressional Democrats offer Republicans several plans to reduce the debt by trillions of dollars. GOP officials not only refuse, but counter with alternatives that make the debt worse.

November 2011: The national debt tops $15 trillion. Republicans, hoping Americans ignore the previous 30 years, blame Democrats.

And as for the specific charge that Obama is to blame, let's just look at Bush v. Obama:

Numbers don't lie.