Larry Summers has joined the growing list of people saying that Mitt Romney's tax plan just does not work.

"It’s easy to say that 'My plan is to eat ice cream sundaes and chocolate cake and hamburgers as much as I want, my plan is to lose 60 pounds, and my plan is to avoid painful exercise, and those are all my objectives and I'm committed to every one of them,'" the former top economic adviser to President Barack Obama said Thursday at the Center for American Progress, a left-leaning think tank. "You don't know quite where you're going to go if you've got all three of those objectives."

"This is the first time that the challenger's errors have, on my accounting, been measured in the trillions of dollars. This is daughter of voodoo economics," the Harvard economist said.

Romney plans to slash taxes in a way that would largely benefit the rich and deprive the government of hundreds of billions of dollars in revenue, while also claiming that his tax plan will not increase the deficit. Romney has promised to additionally reduce the deficit and slash government spending by 18 to 26 percent.

Though Romney has promised to slash both marginal tax rates and corporate tax rates, among other changes, he has been vague about which tax loopholes he would close to make up for revenue lost as a result. Lately, Romney has obscured the idea that he would cut taxes for the rich.

"I'm not going to reduce the share of taxes paid by high-income people," Romney said at the first presidential debate last week, a statement he echoed Tuesday on CNN.

Whether Romney's tax plan adds up has become a subject of contentious debate. The Tax Policy Center concluded in a recent study that Romney's tax plan is impossible without raising taxes on the middle class. But Princeton economics professor Harvey Rosen found that Romney's tax plan is mathematically possible without raising taxes on the middle class, assuming that Americans' incomes grow.

(Hat tip: ThinkProgress' Josh Dorner.)

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  • The Deficit Has Grown Mostly Because Of The Recession

    The deficit has ballooned not because of specific spending measures, but <a href="http://research.stlouisfed.org/fred2/graph/?s[1][id]=FYFSD" target="_hplink">because of the recession</a>. <a href="http://www.whitehouse.gov/omb/budget/Historicals" target="_hplink">The deficit more than doubled</a> between 2008 and 2009, as the economy was in free fall, since laid-off workers paid less in taxes and needed more benefits. The deficit then shrank in 2010 and 2011.

  • The Stimulus Cost Much Less Than Bush's Wars, Tax Cuts

    Republicans frequently have blamed <a href="http://projects.nytimes.com/44th_president/stimulus" target="_hplink">the $787 billion stimulus</a> for the national debt, but, when all government spending is taken into account, the stimulus frankly wasn't that big. In contrast, <a href="http://www.huffingtonpost.com/2011/06/29/cost-of-war-iraq-afghanistan_n_887084.html" target="_hplink">the U.S. will have spent nearly $4 trillion</a> on wars in the Middle East by the time those conflicts end, according to a recent report by Brown University. <a href="http://www.washingtonpost.com/blogs/fact-checker/post/revisiting-the-cost-of-the-bush-tax-cuts/2011/05/09/AFxTFtbG_blog.html" target="_hplink">The Bush tax cuts have cost nearly $1.3 trillion</a> over 10 years.

  • The Deficit Grew Under George W. Bush

    When George W. Bush took office, <a href="http://www.whitehouse.gov/omb/budget/Historicals" target="_hplink">the federal government was running a surplus</a> of $86 billion. When he left, that had turned into a $642 billion deficit.

  • The Deficit Is Shrinking

    <a href="http://www.whitehouse.gov/omb/budget/Historicals" target="_hplink">Last year's federal budget deficit</a> was 12 percent lower than in 2009, according to the Office of Management and Budget.<a href="http://www.whitehouse.gov/omb/budget/Historicals" target="_hplink">The deficit is projected to shrink</a> even more over the next several years.

  • Investors Are Paying Us To Borrow Money

    <a href="http://www.treasury.gov/resource-center/data-chart-center/interest-rates/Pages/TextView.aspx?data=realyield" target="_hplink">The interest rate on 10-year Treasury bonds</a> is <em>negative</em>, according to the Treasury Department. Investors are even paying us for 30-year Treasury bonds, when adjusted for inflation.

  • Investors Are Not Running Away

    <a href="http://www.businessinsider.com/niall-ferguson-has-been-wrong-on-economics-2012-8" target="_hplink">Conservative commentators</a> have been warning for years that investors will run away from Treasury bonds because of the national debt. So far it's not happening. <a href="http://www.huffingtonpost.com/2012/05/30/treasury-yield-record-low_n_1555975.html" target="_hplink">Interest rates on Treasury bonds</a> continue to hover at historic lows.

  • Health Care Reform Reduces The Deficit

    <a href="http://www.huffingtonpost.com/2012/09/04/republican-platform-2012-factual-mistakes_n_1840795.html#slide=1461142" target="_hplink">Republicans have blasted the Affordable Care Act</a> as "budget-busting." But <a href="http://www.huffingtonpost.com/2012/09/04/republican-platform-2012-factual-mistakes_n_1840795.html#slide=1461142" target="_hplink">health care reform actually reduces the deficit</a>, according to the Congressional Budget Office.

  • The U.S. Is Borrowing Less From China

    <a href="http://krugman.blogs.nytimes.com/2012/08/30/fear-of-china-syndrome/" target="_hplink">The U.S. government is borrowing much less from foreign countries</a> than before the recession, according to government data cited by Paul Krugman. That is because the U.S. private sector is financing our bigger deficits.

  • We Spend A Lot On Defense

    <a href="http://www.cbpp.org/cms/index.cfm?fa=view&id=1258" target="_hplink">Defense spending constituted 20 percent</a> of federal spending last year, or $718 billion, according to the Center on Budget and Policy Priorities. This adds up to <a href="https://twitter.com/AJInsight/statuses/241269134996959234" target="_hplink">41 percent of the world's defense spending</a>, according to Bloomberg TV anchor Adam Johnson. <a href="http://www.huffingtonpost.com/2012/07/19/mitt-romney-military-budget_n_1687601.html" target="_hplink">Mitt Romney has vowed</a> to not cut defense spending if elected president.

  • We Spend A Lot On Health Care

    <a href="http://www.cbpp.org/cms/index.cfm?fa=view&id=1258" target="_hplink">Health insurance, including Medicare and Medicaid, constituted 21 percent</a> of federal spending last year. In contrast, education constituted 2 percent of federal spending. Meanwhile, <a href="http://www.miamiherald.com/2012/08/19/2956609/middle-aged-blues-over-paul-ryans.html" target="_hplink">Mitt Romney and Paul Ryan have promised not to change Medicare</a> for Americans age 55 and older.

  • Republicans May Want Large Deficits For Now

    <a href="http://www.businessinsider.com/corporate-taxes-deficits-and-labor-vs-capital-during-reagans-first-term-2012-7" target="_hplink">The federal budget deficit ballooned</a> under Ronald Reagan, and that may be just the way Republicans like it. <a href="http://www.forbes.com/2010/05/06/tax-cuts-republicans-starve-the-beast-columnists-bruce-bartlett.html" target="_hplink">Some Republican thinkers</a> have proposed <a href="http://www.nytimes.com/2010/02/22/opinion/22krugman.html" target="_hplink">"starving the beast"</a>: that is, cutting taxes in order to use larger deficits to justify spending cuts later. Since Republicans ultimately want lower taxes and a smaller government, what better way is there to cut spending than to make it look urgent and necessary?