WASHINGTON — It sounds so surgical, so precise, exactly the kind of air attack that only the U.S. Air Force can execute.

华盛顿——听起来像是外科手术式的，极为精确，是那种只有美国空军才能执行的空袭。

A series of B-2 bombers lifts off from Whiteman Air Force Base in Missouri or the island of Diego Garcia in the Indian Ocean. Refueled in the air, they head for a remote mountain in north-central Iran, far from civilians, where they get Iran’s most heavily fortified nuclear site, Fordo, in their sights.

一系列B-2轰炸机从密苏里州的怀特曼空军基地或印度洋的迪戈加西亚岛起飞。在空中加油后前往伊朗中北部一个远离平民的偏远山区，打击伊朗戒备最森严的核设施——福尔多。

They drop their giant, 30,000-pound bunker-busters, one after another, blasting a giant hole down to the centrifuge halls that have been in the bull’s-eye of the U.S. military since President Barack Obama and the leaders of Britain and France revealed the existence of the plant in the fall of 2009, charging Iran with a great “deception.”

它们一个接一个地投下重约1.3万公斤的巨型钻地炸弹，把离心机房炸出一个大洞。自从奥巴马总统和英法领导人在2009年秋天揭露了该核基地的存在，指责伊朗设下了一个巨大“骗局”以来，这些离心机房一直是美国军方的靶心。

Few potential operations, with the possible exception of a Chinese invasion of Taiwan, have been so examined, rehearsed and debated. Technically, the military and geological experts say, it should be doable.

除了中国入侵台湾之外，很少有什么潜在的行动经过如此严密的检验、演练和辩论。军事和地质专家说，从技术上讲，这应该是可行的。

And yet it is full of risks — known unknowns and unknown unknowns, as former Defense Secretary Donald Rumsfeld used to say in the context of the Iraq War, another rabbit hole of U.S. military action in the Middle East. That is why it has given pause to every American president who has looked at it for the past 16 years.

但也充满了风险——正如前国防部长唐纳德·拉姆斯菲尔德在谈到伊拉克战争——美国在中东军事行动的又一个泥潭——时说的那样，存在已知的未知，还有未知的未知。正因如此，过去的16年里，每一位研究过这个问题的美国总统都会犹豫。

President Donald Trump on Wednesday emphasized that he had yet to make a decision to drop what in private he calls “the big one.” But gone was the bellicose tone that characterized his public utterances a day earlier. In its place was a note of caution. “I may do it,” he told reporters on the White House’s South Lawn. “I may not do it. I mean, nobody knows what I’m going to do.”

特朗普总统周三强调，他还没有决定是否要放弃他私下所说的“重大打击”。但一天前，他在公开讲话时，那种好斗的语气已经消失了。取而代之的是一种谨慎。“我可能会这么做，”他在白宫南草坪对记者说。“我可能不会这么做。我的意思是，没有人知道我要做什么。”

Meanwhile, the Iranians, after five days of remarkable losses to the Israelis, seemed to be looking for a way out. Iran’s supreme leader, Ayatollah Ali Khamenei, issued a defiant response to Trump’s call for “unconditional surrender,” but Trump said there were indications that the Iranians wanted to talk, and reports of an official Iranian plane landing in Oman, where many of the negotiations with Steve Witkoff, the president’s special envoy, had taken place before Israel’s attack.

与此同时，在遭遇以色列方面五天打击并损失惨重后，伊朗方面似乎正在寻找出路。伊朗最高领袖哈梅内伊对特朗普“无条件投降”的呼吁做出了挑衅的回应，但特朗普表示，有迹象表明，伊朗人想要谈判，有报道称，一架伊朗官方飞机降落在阿曼，在以色列袭击之前，伊朗与美国总统特使史蒂夫·维特科夫的许多谈判都是在阿曼进行的。

If Trump is taking a pause, it may be because the list of things that could go wrong is long, and probably incomplete. There’s the obvious: It’s possible that a B-2 could get shot down, despite Israel’s success of taking out so many of Iran’s air defenses. It’s possible the calculations are wrong, and even the United States’ biggest conventional bomb can’t get down that deep.

如果特朗普暂停打击，那可能是因为可能出错的环节有很多，而且可能还有很多未知。显而易见的是：尽管以色列成功地摧毁了伊朗的许多防空系统，但B-2仍有可能被击落。有可能计算是错误的，即使是美国最大的常规炸弹也无法到达那么深的地方。

“I’ve been there, it’s half a mile underground,” Rafael Grossi, the director general of the International Atomic Energy Agency, said last week, as the Israeli operation began.

“我去过那里，它在地下半英里，”国际原子能机构总干事拉斐尔·格罗西上周在以色列的行动开始时说。

But assuming that the operation itself is successful, the largest perils may lie in the aftermath, many experts say, just as they did in Afghanistan and Iraq. There are many lessons from that ugly era of misbegotten American foreign policy, but the most vital may be that it’s the unknown unknowns that can come back to bite.

但是，许多专家说，假设这次行动本身是成功的，那么最大的危险可能在于其后果，就像在阿富汗和伊拉克一样。从那个美国拙劣外交政策的丑陋时代中，我们可以吸取很多教训，但最重要的可能是，“未知的未知”可能会反咬一口。

“Subcontracting the Fordo job would put the United States in Iran’s sights,” Daniel C. Kurtzer, a former U.S. ambassador to Israel, and Steven N. Simon, a veteran of the National Security Council, wrote in Foreign Affairs on Wednesday. “Iran would almost certainly retaliate by killing American civilians. That, in turn, would compel the United States to reciprocate.”

“把福尔多的工作外包出去，会让美国进入伊朗的视线，”前美国驻以色列大使丹尼尔·库尔策和国家安全委员会资深官员史蒂文·西蒙周三在《外交事务》上写道。“伊朗几乎肯定会通过杀害美国平民进行报复。反过来，这将迫使美国做出回应。”

“Soon enough,” they continued, “the only targets left for Washington to hit would be the Iranian regime’s leaders, and the United States would again go into the regime-change business — a business in which exceedingly few Americans want to be involved any longer.”

“很快，”他们继续说，“唯一可以打击的目标将只剩伊朗政权的领导人，而美国将再次卷入政权更迭的勾当——一项很少有美国人愿意再参与的事。”

The reaction could take other forms. Iran is skilled at terrorism, and reacted to the U.S.-Israeli cyber attack on its nuclear program 15 years ago by building a fearsome cyber corps, not as stealthy as China’s or as bold as Russia’s, but capable of considerable damage. And it has plenty of short-range missiles left to attack oil tankers, making transit in the Persian Gulf too risky.

这种反应可能以其他的形式呈现。伊朗擅长恐怖主义，15年前，美国和以色列对其核项目发动网络攻击时，伊朗建立了一支可怕的网络部队，虽然不像中国的那样隐秘，也不像俄罗斯的那样大胆，却能造成相当大的破坏。此外，伊朗还有大量的短程导弹可以用来攻击油轮，使得在波斯湾的航行过于危险。

The last thing the White House wants to do is air these risks in public. Democrats are calling for a congressional role, but they have no power to compel it. “Given the potential for escalation, we must be brought into this decision,” Sen. Adam Schiff of California, one of Trump’s political rivals, said on CNN on Wednesday. “Bombing Fordo would be an offensive activity.”

白宫最不愿意做的就是在公众面前宣扬这些风险。民主党人呼吁国会发挥作用，但他们没有权力强迫国会发挥作用。“考虑到事态升级的可能性，我们必须参与决策，”特朗普的政治对手之一、加州参议员亚当·希夫周三在CNN说。“轰炸福尔多将是一种进攻行为。”

And history suggests that nuclear programs can be bombed, but not eliminated.

历史表明，核项目可以被轰炸，但不能被消除。

“Nuclear weapons can be stopped through force — the Syrian program is a good example,’’ said Gary Samore, who was the Obama administration’s coordinator for weapons of mass destruction when the existence of the Fordo plant was made public. (It was discovered toward the end of the Bush administration.)

“核武器可以通过武力来制止，叙利亚的核项目就是一个很好的例子，”加里·萨莫尔说。当福尔多核工厂的存在被公之于众时，他是奥巴马政府的大规模杀伤性武器问题协调员。（该工厂是在布什政府即将结束时发现的。）

And in Iraq, after the Israelis bombed the Osirak reactor in 1981, to keep Saddam Hussein from getting the fuel for a bomb, the Iraqis “reacted by building a huge, secret program” that went undetected until after the Gulf War in 1991, Samore said. That was such an embarrassment to American intelligence agencies that more than a decade later they wildly overestimated his ability to do it again, contributing to the second failure — and leading the United States into the Iraq War.

萨莫尔说，1981年在伊拉克，为阻止萨达姆·侯赛因获得制造核弹的燃料，以色列轰炸了奥西拉克反应堆，伊拉克人“建立了一个庞大的秘密项目作为回应”，直到1991年海湾战争结束后才被发现。这让美国情报机构非常尴尬，以至于十多年后，他们过分高估了萨达姆·侯赛因再次这样做的能力，导致了第二次失败——并将美国带入了伊拉克战争。

But Samore added: “I can’t think of a case where air power alone was sufficient to end a program.”

但萨莫尔还说：“我想不出在哪个案例中，仅靠空中力量就足以结束一个项目。”

That is an important consideration for Trump. He must decide in the next few days whether Israel’s attacks on Iran’s Natanz enrichment facility, and its bombing of workshops where new centrifuges are made and laboratories where weapons research may have been taking place, are sufficient to set back the Iranian program.

这是特朗普的一个重要考虑因素。他必须在未来几天内决定，以色列对伊朗纳坦兹铀浓缩设施的袭击，以及对制造新离心机的厂房和可能正在进行武器研究的实验室的轰炸，是否足以挫败伊朗的核项目。

In short, he must decide whether it is worth the huge risk of direct American involvement for whatever gain would come from destroying Fordo with American pilots, American warplanes and American weapons.

简而言之，他必须决定，用美国飞行员、美国战机和美国武器摧毁福尔多所能获得的任何收益，是否值得冒着美国直接介入的巨大风险。

But he also doesn’t want to be accused of missing the chance to set the Iranians back by years. “If this war ends and this Fordo is left intact,” said Samore, now a professor at Brandeis University, “then it wouldn’t take long to get this going again.”

但他也不想被指责错过了让伊朗倒退数年的良机。“如果这场战争结束后，福尔多被完好无损地保存下来，”现任布兰代斯大学教授的萨莫尔说，“那么不需要很长时间，它就能重新启动。”