导读：波士顿大学经济学教授劳伦斯-克特里考夫(Laurence Kotlikoff)8月11日在彭博网发表专栏文章称，巨大的财政缺口意味着美国事实上已经破产，这一缺口主要来自于社会保障和医疗支出。以下是劳伦斯-克特里考夫的专栏文章：
　　让我们面对现实吧，美国已经破产，无论增加支出还是降低税收都无助于这个国家偿还债务。
　　现在美国能够做和必须做的事情是，大刀阔斧地简化其税收、医疗、退休和金融机制，现在这几个领域仍是一团乱麻。然而这是一个好消息。它意味着这些领域均可以被重新设计，令其成本大幅下降又无碍于达到其合理目的，同时在此过程之中让经济获得新生。
　　上个月，国际货币基金组织发布了对美国经济政策的年度评述。报告在摘要部分对美国财政政策作出温和的批评：“委员们对美国政府稳定财政的承诺表示欢迎，但认为需要采取比当前预算力度更大的调整才能让债务与GDP的比率企稳。”
　　但如果深入研读，你会发现IMF事实上已经宣布美国破产。在《2010年7月特定问题论述》的“第6部分”有这么一句话：“按照一定的贴现率，与今日联邦财政政策相关的财政缺口相当巨大。”并称：“填补财政缺口需要经年累月的财政调整，每年的调整幅度应相当于美国GDP的14%。”
　　国内生产总值的14%是什么一个概念？目前联邦收入占GDP的比重为14.9%。因此IMF的意思是，要填补美国的财政缺口，大致而言，在财政收入方面，需要立即将我们的个人所得税率、企业所得税率、联邦税率以及《联邦保险贡献法案》项下的税率立即翻倍并长期保持下去。
　　如此增税举措将使得美国今年实现相当于国内生产总值5%的财政盈余，而非现在9%的赤字。因此IMF实际上是说，美国目前和未来数年必须实现巨大的财政盈余，才能为计划中的支出买单。另一层意思也显而易见，如果美国迟迟不肯痛下决心进行财政调整，等待我们的将是“长痛”。
　　难道IMF在胡说？非也，它的话句句属实。国会预算办公室6月份发布的《长期预算前瞻》反映出来的问题甚至更大。
　　根据国会预算办公室的数据，我计算出财政缺口为202万亿美元，是官方公布的债务数字的15倍以上。我们的“官方”债务与实际净负债之间的巨大差异是不足为奇的，它反映了经济学家所谓的“贴标签问题”。近年来国会一直小心翼翼地将其大部分负债贴上“非官方”的标签，让它们远离账面并留给未来。
　　举例来说，《联邦保险贡献法案》项下的社会保障缴款被称之为税收，而我们未来的社会保障福利被称为转移支付。政府也完全可以将我们的缴款唤作“贷款”，将未来的社保福利称为“扣除老年税之后的贷款偿还”，这些缴款的本金加利息与所承诺的社保福利之间的差额便是老年税。
　　财政缺口并不受财政标签的影响，它是衡量我们长期财政状况唯一理论上正确的方法，因为它将所有支出都考虑在内了，不论这些支出被贴上何种标签，同时综合了长期和短期政策。
　　财政缺口为何如此巨大？很简单。我们有7800万“婴儿潮”世代人，他们在彻底退休之后将享受高于人均GDP的社会保障和医疗保险福利。这些权利的年均成本按今日货币计算大约为4万亿美元。不错，20年后我们的经济规模将会增长，但并这不足以让我们年复一年地承受如此之重负。
　　要理解这一问题，你可以设想一个运作长达60年的惊天“庞氏骗局”：不断地从年轻人那里拿走更多资源，给予老年人，同时向年轻人承诺，他们这笔资金转移最终可以获得回报。
　　里根总统时期经济顾问委员会主席赫伯-斯坦(Herb Stein)有一句广为传诵的名言：“不可持续的东西必将终止。”诚然。“山姆大叔”的“庞氏骗局”必将终止，但也必将终止得太晚。
　　而且它将以非常可怕的方式停止。第一种可能是“婴儿潮”世代的退休福利被大幅削减，第二种可能是年轻人面临直上云霄的税率上升，让他们丧失工作和储蓄的动力，第三种可能则是政府拼命印钞票来支付它的账单。
　　我们最有可能看到的是三者的结合，这最终会导致贫困人口、税率、利率和消费者价格急剧飙升。这是一条崎岖的下山之路，但我们已经上路了。一旦那些债券持有人从梦中醒来、意识到美国的财政状况远逊希腊，他们会把我们一脚踢下山去。
　　一些信奉凯恩斯主义教条的经济学家可能会说，未来几年的任何刺激政策都不会影响我们应对长期赤字的能力。
　　这种说法是一个简单的算术错误。财政缺口是政府的信用卡账单，这一账单每年的利息为GDP的14%。如果美国不能支付今年的利息，这笔钱将被加进余额当中。
　　需求派称如果今年暂不实行14%的财政紧缩，反而继续扩大支出，将促进经济增长和提高财政收入，从而足以弥补支出。
　　我对此作何反应？面对现实，或者支持同样受到迷惑的供给派。我们的国家已经破产，再也无法承受所谓有利无弊的“解决方案”之害。

　　以下是英语原文：
　　U.S. Is Bankrupt and We Don't Even Know It: Laurence Kotlikoff
　　Let’s get real. The U.S. is bankrupt. Neither spending more nor taxing less will help the country pay its bills.
What it can and must do is radically simplify its tax, health-care, retirement and financial systems, each of which is a complete mess. But this is the good news. It means they can each be redesigned to achieve their legitimate purposes at much lower cost and, in the process, revitalize the economy.
Last month, the International Monetary Fund released its annual review of U.S. economic policy. Its summary contained these bland words about U.S. fiscal policy: “Directors welcomed the authorities’ commitment to fiscal stabilization, but noted that a larger than budgeted adjustment would be required to stabilize debt-to-GDP.”
But delve deeper, and you will find that the IMF has effectively pronounced the U.S. bankrupt. Section 6 of the July 2010 Selected Issues Paper says: “The U.S. fiscal gap associated with today’s federal fiscal policy is huge for plausible discount rates.” It adds that “closing the fiscal gap requires a permanent annual fiscal adjustment equal to about 14 percent of U.S. GDP.”
The fiscal gap is the value today (the present value) of the difference between projected spending (including servicing official debt) and projected revenue in all future years.
Double Our Taxes
To put 14 percent of gross domestic product in perspective, current federal revenue totals 14.9 percent of GDP. So the IMF is saying that closing the U.S. fiscal gap, from the revenue side, requires, roughly speaking, an immediate and permanent doubling of our personal-income, corporate and federal taxes as well as the payroll levy set down in the Federal Insurance Contribution Act.
Such a tax hike would leave the U.S. running a surplus equal to 5 percent of GDP this year, rather than a 9 percent deficit. So the IMF is really saying the U.S. needs to run a huge surplus now and for many years to come to pay for the spending that is scheduled. It’s also saying the longer the country waits to make tough fiscal adjustments, the more painful they will be.
Is the IMF bonkers?
No. It has done its homework. So has the Congressional Budget Office whose Long-Term Budget Outlook, released in June, shows an even larger problem.
‘Unofficial’ Liabilities
Based on the CBO’s data, I calculate a fiscal gap of $202 trillion, which is more than 15 times the official debt. This gargantuan discrepancy between our “official” debt and our actual net indebtedness isn’t surprising. It reflects what economists call the labeling problem. Congress has been very careful over the years to label most of its liabilities “unofficial” to keep them off the books and far in the future.
For example, our Social Security FICA contributions are called taxes and our future Social Security benefits are called transfer payments. The government could equally well have labeled our contributions “loans” and called our future benefits “repayment of these loans less an old age tax,” with the old age tax making up for any difference between the benefits promised and principal plus interest on the contributions.
The fiscal gap isn’t affected by fiscal labeling. It’s the only theoretically correct measure of our long-run fiscal condition because it considers all spending, no matter how labeled, and incorporates long-term and short-term policy.
$4 Trillion Bill
How can the fiscal gap be so enormous?
Simple. We have 78 million baby boomers who, when fully retired, will collect benefits from Social Security, Medicare, and Medicaid that, on average, exceed per-capita GDP. The annual costs of these entitlements will total about $4 trillion in today’s dollars. Yes, our economy will be bigger in 20 years, but not big enough to handle this size load year after year.
This is what happens when you run a massive Ponzi scheme for six decades straight, taking ever larger resources from the young and giving them to the old while promising the young their eventual turn at passing the generational buck.
Herb Stein, chairman of the Council of Economic Advisers under U.S. President Richard Nixon, coined an oft-repeated phrase: “Something that can’t go on, will stop.” True enough. Uncle Sam’s Ponzi scheme will stop. But it will stop too late.
And it will stop in a very nasty manner. The first possibility is massive benefit cuts visited on the baby boomers in retirement. The second is astronomical tax increases that leave the young with little incentive to work and save. And the third is the government simply printing vast quantities of money to cover its bills.
Worse Than Greece
Most likely we will see a combination of all three responses with dramatic increases in poverty, tax, interest rates and consumer prices. This is an awful, downhill road to follow, but it’s the one we are on. And bond traders will kick us miles down our road once they wake up and realize the U.S. is in worse fiscal shape than Greece.
Some doctrinaire Keynesian economists would say any stimulus over the next few years won’t affect our ability to deal with deficits in the long run.
This is wrong as a simple matter of arithmetic. The fiscal gap is the government’s credit-card bill and each year’s 14 percent of GDP is the interest on that bill. If it doesn’t pay this year’s interest, it will be added to the balance.
Demand-siders say forgoing this year’s 14 percent fiscal tightening, and spending even more, will pay for itself, in present value, by expanding the economy and tax revenue.
My reaction? Get real, or go hang out with equally deluded supply-siders. Our country is broke and can no longer afford no- pain, all-gain “solutions.”
(Laurence J. Kotlikoff is a professor of economics at Boston University and author of “Jimmy Stewart Is Dead: Ending the World’s Ongoing Financial Plague with Limited Purpose Banking.” The opinions expressed are his own.)
To contact the writer of this column: Laurence Kotlikoff at kotlikoff@bu.edu