So new budget projections show a cumulative deficit of $9 trillion over the next decade. According to many commentators, that’s a terrifying number, requiring drastic action — in particular, of course, canceling efforts to boost the economy and calling off health care reform.

The truth is more complicated and less frightening. Right now deficits are actually helping the economy. In fact, deficits here and in other major economies saved the world from a much deeper slump. The longer-term outlook is worrying, but it’s not catastrophic.

The only real reason for concern is political. The United States can deal with its debts if politicians of both parties are, in the end, willing to show at least a bit of maturity. Need I say more?

Let’s start with the effects of this year’s deficit.

There are two main reasons for the surge in red ink. First, the recession has led both to a sharp drop in tax receipts and to increased spending on unemployment insurance and other safety-net programs. Second, there have been large outlays on financial rescues. These are counted as part of the deficit, although the government is acquiring assets in the process and will eventually get at least part of its money back.

What this tells us is that right now it’s good to run a deficit. Consider what would have happened if the U.S. government and its counterparts around the world had tried to balance their budgets as they did in the early 1930s. It’s a scary thought. If governments had raised taxes or slashed spending in the face of the slump, if they had refused to rescue distressed financial institutions, we could all too easily have seen a full replay of the Great Depression.

As I said, deficits saved the world.

In fact, we would be better off if governments were willing to run even larger deficits over the next year or two. The official White House forecast shows a nation stuck in purgatory for a prolonged period, with high unemployment persisting for years. If that’s at all correct — and I fear that it will be — we should be doing more, not less, to support the economy.

But what about all that debt we’re incurring? That’s a bad thing, but it’s important to have some perspective. Economists normally assess the sustainability of debt by looking at the ratio of debt to G.D.P. And while $9 trillion is a huge sum, we also have a huge economy, which means that things aren’t as scary as you might think.

Here’s one way to look at it: We’re looking at a rise in the debt/G.D.P. ratio of about 40 percentage points. The real interest on that additional debt (you want to subtract off inflation) will probably be around 1 percent of G.D.P., or 5 percent of federal revenue. That doesn’t sound like an overwhelming burden.

Now, this assumes that the U.S. government’s credit will remain good so that it’s able to borrow at relatively low interest rates. So far, that’s still true. Despite the prospect of big deficits, the government is able to borrow money long term at an interest rate of less than 3.5 percent, which is low by historical standards. People making bets with real money don’t seem to be worried about U.S. solvency.

The numbers tell you why. According to the White House projections, by 2019, net federal debt will be around 70 percent of G.D.P. That’s not good, but it’s within a range that has historically proved manageable for advanced countries, even those with relatively weak governments. In the early 1990s, Belgium — which is deeply divided along linguistic lines — had a net debt of 118 percent of G.D.P., while Italy — which is, well, Italy — had a net debt of 114 percent of G.D.P. Neither faced a financial crisis.

So is there anything to worry about? Yes, but the dangers are political, not economic.

As I’ve said, those 10-year projections aren’t as bad as you may have heard. Over the really long term, however, the U.S. government will have big problems unless it makes some major changes. In particular, it has to rein in the growth of Medicare and Medicaid spending.

That shouldn’t be hard in the context of overall health care reform. After all, America spends far more on health care than other advanced countries, without better results, so we should be able to make our system more cost-efficient.

But that won’t happen, of course, if even the most modest attempts to improve the system are successfully demagogued — by conservatives! — as efforts to “pull the plug on grandma.”

So don’t fret about this year’s deficit; we actually need to run up federal debt right now and need to keep doing it until the economy is on a solid path to recovery. And the extra debt should be manageable. If we face a potential problem, it’s not because the economy can’t handle the extra debt. Instead, it’s the politics, stupid.

舉債拚經濟 赤字救世界

最新的預算預估顯示，美國未來十年將累積9兆美元赤字。許多評論員說，這是可怕的數字，必須採取激烈的因應措施--當然包括取消振興經濟的努力，和延緩健保改革。

事實上，問題沒有那麼複雜，也沒那麼可怕。此時此刻赤字實際上正在幫助經濟。美國和其他主要經濟體的赤字挽救了世界免於陷入更深的衰退。長期的展望雖令人擔憂，但並沒有那麼悲慘。

唯一讓人擔心的原因是政治。如果兩黨政治人物到最後都願意表現更成熟一點，美國就能應付它的債務。需要我再詳細解說嗎？

我們先從今年赤字的效應談起。

赤字激增有兩大理由。第一，衰退導致稅收劇減，以及失業保險和其他社會安全計畫的支出劇增。第二，金融紓困耗費了鉅額經費。這些都是赤字的一部分，雖然政府在過程中獲得資產，且最後至少能從中收回一部分錢。

這告訴我們，此時有赤字是好事。想想如果美國政府和世界各國的政府嘗試像1930年代那樣平衡預算，會發生什麼事？光想就讓人害怕。如果政府在衰退時加稅或削減支出，如果他們拒絕救援困頓的金融機構，我們很可能早就見到大蕭條的歷史重演。

所以我說，赤字拯救了世界。

事實上，如果政府願意在未來一、兩年承擔更大的赤字，情況可能還會更好。白宮的正式預測顯示，美國將陷於一段長時間的苦難，失業率將居高不下好幾年。如果這個預測正確--我擔心確實會如此--我們應該為支援經濟做更多，而非減少。

但我們負擔的債務怎麼辦？債務不是好事，但重要的是，我們要把視野放遠些。經濟學家評估債務可持續性的方法是，觀察債務對國內生產毛額（GDP）的比率。雖然9兆美元是龐大的數字，我們也有一個龐大的經濟，這表示情況並沒有我們想像的可怕。

我們可以這樣看：我們看到債務／GDP比率上升大約40個百分點。這些增加債務的實質利息（去除通貨膨脹）可能相當於約GDP的1%，或聯邦歲入的5%。這聽起來不像是難以承受的負擔。

好，這是假設美國政府的信用會保持良好，因此能以相當低的利率舉債。截至目前，情況正是如此。儘管預期赤字會居高不下，政府還能以不到3.5%的利率長期借到錢，以歷史標準來看算是很低了。真正在市場上拿錢投資的人，似乎不擔心美國政府的償債能力。

數字會告訴你為什麼。據白宮的預測，到2019年，聯邦的淨債務將達到GDP的約70%。這個數字並不漂亮，但它還維持在歷史證明先進國家可以管理的範圍，即使是相對較弱的政府也能辦到。在1990年代初期，因為多語言而深陷分歧的比利時淨債務高達GDP的118%，而義大利—我是說，義大利—淨債務達114%。兩國都未出現金融危機。

那麼，有什麼該擔心的嗎？有，但危機是出在政治，而非經濟。

我曾經說過，那些十年的預測不像你可能聽到的那樣糟。然而就更長期來看，美國政府除非作出重大改變，未來可能面臨大麻煩，特別是必須控制聯邦醫保（Medicare）和聯邦醫補（Medicaid）的支出。

在整體健保改革的情況下，這應該不是難事。畢竟，美國在醫療上的花費遠多於其他先進國家，但成效卻不見得更好，所以應該能讓我們的體系更具成本效益些。

當然，如果連最溫和的改進體系嘗試都被保守派成功地煽惑，說成是企圖「拔掉老奶奶的插管」，那麼改革體系不可能發生。

所以別為今年的赤字發愁，實際上此刻我們必須增加聯邦債務，必須繼續這麼做，直到經濟踏上堅實的復甦之路，而增加的債務應能善加管理。如果我們面臨了潛在的問題，那不是因為經濟無法處理增加的債務。

問題是出在政治，笨蛋。

原文參照：
http://www.nytimes.com/2009/08/28/opinion/28krugman.html

2009-08-29/經濟日報/A7版/國際焦點 吳國卿譯