President Obama and congressional Democrats are blaming their trillion-dollar budget deficits on the Bush tax cuts of 2001 and 2003. Letting these tax cuts expire is their answer. Yet the data flatly contradict this "tax cuts caused the deficits" narrative. Consider the three most persistent myths:

• The Bush tax cuts wiped out last decade's budget surpluses. Sen. John Kerry (D., Mass.), for example, has long blamed the tax cuts for having "taken a $5.6 trillion surplus and turned it into deficits as far as the eye can see."...