They're not saying. Jonathan Bernstein fumes

Republicans are currently blocking the extension of lower student loan interest rates because they insist on cutting a health care fund to pay for its cost. But when it comes to the Bush tax cuts, they continue to believe that no budget offsets are necessary to pay for them. … You really couldn’t ask for clearer evidence that Republicans are not only wholly uninterested in reducing federal budget deficits, but even oppose the whole notion of considering individual spending and taxing decisions in the context of an overall budget.