With his broad attack on Iran early Saturday morning and his call to the Iranian people to overthrow their government, President Trump has embarked on the ultimate war of choice.

特朗普总统周六清晨对伊朗发动大规模袭击，并呼吁伊朗人民推翻本国政府，由此踏上了典型的选择性战争之路。

He was not driven by an immediate threat. There was no race for a bomb. Iran is further from the capability to build a nuclear weapon today than it has been in several years, thanks largely to the success of the president’s previous strike on Iranian nuclear enrichment sites, in June.

他采取行动并非出于迫在眉睫的威胁。伊朗并没有急于制造核弹。由于特朗普去年6月对伊朗核浓缩设施发动的那次打击，伊朗如今距离具备制造核武器的能力比过去几年都要远。

While Mr. Trump claimed Tehran was ultimately aiming to reach to the United States with its array of missiles, even his own Defense Intelligence Agency concluded last year that it would be a decade before Iran could get past the technological and production hurdles to produce a significant arsenal.

尽管特朗普声称德黑兰的最终目标是利用导弹系统打击美国本土，但就连他自己的国防情报局去年也得出结论：伊朗至少还需要十年时间，才能跨越技术和生产方面的重重障碍打造出一个规模可观的武器库。

And there were no indications of a coming Iranian attack on the United States, its allies or its bases in the region. Instead, Mr. Trump struck the Islamic Republic largely because he apparently sensed a remarkable moment of weakness for the government — and an opportunity for the United States to topple Ayatollah Ali Khamenei and the Islamic Revolutionary Guards Corps after 47 years of episodic confrontations, which he described at length in an eight-minute video.

也没有任何迹象表明伊朗即将对美国、其盟友或该地区的美军基地发动攻击。相反，特朗普之所以对这个伊斯兰共和国动手，很大程度上是因为他显然察觉到伊朗政权正处于一个非同寻常的虚弱时刻，并看到了一个让美国推翻阿亚图拉·阿里·哈梅内伊及伊斯兰革命卫队的契机。此前，双方曾断断续续地对抗了47年，特朗普在一段长达八分钟的视频中对此进行了详尽阐述。

But unlike past presidents putting American forces at risk — and, in an age of terrorism and cyberattacks, perhaps civilians as well — Mr. Trump did not spend months building a case for war. He never presented evidence of an imminent threat, or answered the question of why a nuclear program he claimed he had “obliterated” eight months ago was now on the brink of revival.

但不同于以往那些让美军（在恐怖主义和网络攻击时代或许也包括平民）置于危险境地的总统，特朗普并未花费数月时间为这场战争构建理由。他从未拿出证据证明威胁的紧迫性，也没有回答这样一个问题：为何他在八个月前声称已被自己“彻底摧毁”的核计划如今却又濒临重启。

His pretaped video, released in the middle of the night as the missiles started exploding in Tehran, recited a list of long-running grievances with Iran, including its brutal use of terror. But he never explained why in the pantheon of threats facing the United States, including an already-nuclear-armed North Korea and the expanding nuclear arsenals and territorial ambitions of Russia and China, a weakened Iran ranks first.

他预先录制的视频在深夜时分发布，当时德黑兰正传出爆炸声，视频罗列了美国长期以来对伊朗的种种不满，包括伊朗残酷使用恐怖主义。但他从未解释，在美国面临的诸多威胁中——其中既有已经拥核的朝鲜，也有核武库不断扩张、领土野心日益膨胀的俄罗斯和中国——一个被削弱的伊朗为何会位居首位。

周六，德黑兰发生爆炸，现场升起浓烟。

So in choosing this moment, and this vector of attack, a man who came to office promising an end to reckless military interventions — and wars intended to prompt regime change — is taking a huge risk. There are few, if any, examples in history of toppling the government of a large nation — in this case about 90 million people — with air power alone. Mr. Trump, however, was already celebrating success, announcing on social media that Ayatollah Khamenei was dead.

因此，选择此时此刻、以这种方式发动攻击，这位上任时曾承诺结束鲁莽军事干预、反对以政权更迭为目的的战争的领导人无疑是在冒巨大的风险。历史上几乎找不到仅凭空中力量就推翻一个人口约9000万的大国政府的先例。不过，特朗普已经开始庆祝胜利，他在社交媒体上宣布阿亚图拉哈梅内伊已死。

And yet Mr. Trump has made clear that is his plan. He has no intention, administration officials have insisted, of sending in ground troops to finish the job, the invitation to the “forever wars” that he campaigned against.

他还明确表示，这就是他的计划。政府官员坚称，他无意派遣地面部队完成任务，也无意挑起他竞选时所反对的“无休止的战争”。

“The idea that we’re going to be in a Middle Eastern war for years with no end in sight — there is no chance that will happen,” Vice President JD Vance, who is famously skeptical of American military interventions and openly called for the United States to withdraw support from Ukraine, told The Washington Post days before the attack on Iran.

“认为我们将陷入一场旷日持久、看不到尽头的中东战争的想法——这绝不可能发生，”副总统JD·万斯在伊朗遭袭击前几天告诉《华盛顿邮报》。万斯素来对美国的军事干预持怀疑态度，并公开呼吁美国撤回对乌克兰的支持。

So Mr. Trump’s strategic bet rides almost entirely on the ability of the Iranian people, largely unarmed and unorganized, to seize the moment and overthrow a government that millions of them find both brutal and odious. The protests that filled the streets of Iranian cities, and led to a crackdown that killed thousands, gave him his chance.

因此，特朗普的战略赌注几乎完全押在了伊朗人民身上，寄希望于这些大多手无寸铁、组织涣散的民众抓住时机，推翻一个被数百万人视为残暴可憎的政府。伊朗国内的抗议活动给了他这个机会，这些抗议席卷了各大城市，但随后受到镇压，导致数千人丧生。

一张发布在社交媒体上的图片显示1月在德黑兰举行的示威活动。

But if Mr. Trump and Prime Minister Benjamin Netanyahu of Israel, who urged him starting in December to launch this war, and who joined in it from the start, have a plan to accomplish that goal, they have yet to reveal it, even to their closest allies.

但如果特朗普和以色列总理本雅明·内塔尼亚胡——后者从去年12月起就敦促他发动这场战争，并从一开始便参与其中——确实有一套实现这一目标的计划，那么迄今为止，他们尚未向任何人披露，甚至包括他们最亲密的盟友。

Senior officials of three of those allies, ranging from Europe to the Gulf and interviewed in the past few days, said that in their interactions with Mr. Trump’s top aides, they heard little enthusiasm for these attacks, and no plausible legal justification for striking Iran now. Those officials spoke on condition of anonymity to describe private discussions. But their experience partly explains why Britain, America’s closest ally, barred the United States from using Diego Garcia and bomber bases in Britain to launch American fighters and bombers.

过去几天，欧洲和海湾地区的三个盟友的高级官员在接受采访时表示，在与特朗普高级助手的交流中，他们几乎没有感受到对这些袭击的热情，也看不到现在打击伊朗有任何站得住脚的法律依据。这些官员要求匿名，以描述私下讨论的内容。但他们的经历在一定程度上解释了为什么英国——美国最亲密的盟友——禁止美方使用迪戈加西亚基地以及英国境内的轰炸机基地来起飞美国战斗机和轰炸机。

“It is not as if Iran poses a threat to our interests that it hadn’t for 47 years,” said Richard N. Haass, the former president of the Council on Foreign Relations and the author of the 2009 book “War of Necessity, War of Choice,” a study of the two conflicts with Iraq, in 1991 and 2003. The first, he concluded, was defined by narrow and achievable aims: liberating Kuwait after Saddam Hussein invaded. Once Iraq was driven from Kuwaiti territory, George H.W. Bush decided against overthrowing Hussein.

“并不是说伊朗现在对我们的利益构成了过去47年里从未存在过的威胁，”外交关系委员会前主席、曾于2009年出版研究1991年和2003年两次伊拉克战争的《必然之战，选择之战》(War of Necessity, War of Choice)一书的理查德·哈斯说。他认为，第一次战争的目标明确且可实现：在萨达姆·侯赛因入侵后解放科威特。一旦伊拉克被逐出科威特领土，老布什就决定不再推翻侯赛因政权。

But Mr. Trump’s decision on Saturday was more like George W. Bush’s decision to rid the world of Hussein and his government, because of the long-festering threat it posed to international peace.

但特朗普周六的决定更像小布什当年试图铲除侯赛因及其政府的决定，理由是其长期以来对国际和平构成威胁。

周六，德黑兰发生数轮爆炸，人们四处奔逃。

“As in the second Iraq war, there wasn’t a necessity to attack Iran, there was an opportunity,” Mr. Haass said. “This is a classic preventive attack, to keep Iran from gaining a capability in the future. What’s missing is ‘why now?’ because there were other choices: diplomatic accords under military pressure, economic embargoes, interceptions of Iranian ships.”

“就像第二次伊拉克战争一样，攻击伊朗并非出于必要，而是因为出现了机会，”哈斯说。“这是一场典型的预防性打击，目的是阻止伊朗在未来获得某种能力。而缺失的是‘为什么是现在？’因为还有其他选择：在军事压力下达成外交协议、实施贸易禁运、拦截伊朗船只。”

In international law, the difference between a war of necessity and a war of choice is huge. A pre-emptive strike — where one nation sees an attack massing across the river or the ocean and strikes first — is considered legitimate.

在国际法中，必然之战和选择之战的差别巨大。先发制人的打击——即一国发现敌对力量在河对岸或海那头集结兵力，因而率先发动攻击——被视为合法。

A preventive strike, in which the powerful hit the weaker state, is considered illegal. An example would be Russia’s decision to invade Ukraine, which the United States and much of the world denounced as a gross violation of the international order.

预防性打击——即强国对较弱国家动手——则被认为是非法的。例如，俄罗斯入侵乌克兰的决定就遭到了美国和世界上大多数国家的谴责，认为此举严重违反国际秩序。

Mr. Trump’s response is that he did not need a precipitating event. He ran through more than four decades of deadly Iranian actions — from the 1979 hostage crisis, which lasted 444 days, to attacks on American bases and ships. “We’re not going to put up with it any longer,” Mr. Trump said in a recorded video he posted on his social media account. And even the Pentagon’s name for the mission, Operation Epic Fury, seemed to reflect the accumulation of grievances.

特朗普的回应是，他并不需要什么导火索。他回顾了伊朗四十多年来的种种致命行径：从持续444天的1979年人质危机到对美军基地和舰船的袭击。“我们不会再忍下去了，”特朗普在发布于社交媒体上的一段录制视频中说。甚至连五角大楼为此次行动起的名字——“史诗之怒行动”——似乎都反映了这种长期积累的不满。

The international legal ramifications are not likely to influence Mr. Trump’s view of the attack. “I don’t need international law,” he told four reporters from The New York Times during an interview in January. “I’m not looking to hurt people.” And he added that while he thought his administration should abide by international legal principles, he made it clear he would be the arbiter of when those principles applied to the United States.

国际法层面的影响不太可能左右特朗普对这次攻击的看法。“我不需要国际法，”他在1月接受《纽约时报》四名记者采访时说。“我不是为了伤害任何人。”他还补充说，虽然他认为自己的政府应当遵循国际法原则，但也明确表示，何时适用这些原则将由他本人裁定。

“It depends on what your definition of international law is,” he said.

“这取决于你如何定义国际法，”他说。

It may also depend on what the definition of “war” is. In his statement, Mr. Trump called this action a war, warning the country that it may have to confront casualties. But he made no effort to seek an authorization to use military force, much less a war declaration, from Congress.

这或许也取决于如何定义“战争”。在声明中，特朗普将此次行动称为一场战争，警告国家可能需要面对人员伤亡。但他并未试图寻求国会授权使用武力，更不用说正式的宣战声明。

He would certainly not be the first president to initiate a major military action without formal approval from Congress. But in Mr. Trump’s case, he has dismissed the thought that he even needs it.

他当然不是第一位在未获国会正式批准的情况下发动重大军事行动的总统。但就特朗普而言，他根本不认为自己需要这样做。

特朗普总统预先录制的视频列举了对伊朗由来已久的诸多不满。

When historians look back at this moment, they are likely to ask two questions: Why did Mr. Trump act now, and why was Iran his target?

当历史学家回顾这一时刻时，他们很可能会提出两个问题：特朗普为何选择现在行动？以及为何以伊朗为目标？

In the end, Mr. Trump’s venture — his seventh attack on a foreign nation since he came to office — may be judged by whether it ignores the Churchill rule.

最终，特朗普的这次冒险——他上任以来对外国发动的第七次攻击——或将以其是否无视“丘吉尔法则”而被评判。

Long before he became Britain’s wartime prime minister, Winston Churchill wrote about his youth, as a journalist and sometime participant in wars. “Never, never, never believe any war will be smooth and easy, or that anyone who embarks on the strange voyage can measure the tides and hurricanes he will encounter,” he wrote in “My Early Life.”

早在成为英国战时首相之前，温斯顿·丘吉尔在回忆自己年轻时作为记者偶尔参与战争的经历时写道：“永远、永远、永远不要相信任何一场战争会顺利而轻松，也不要以为踏上这段奇异航程的人，能够预知自己将遭遇的潮汐与飓风，”他在《我的早年生活》中这样写道。

“The statesman who yields to war fever must realize that once the signal is given, he is no longer the master of policy but the slave of unforeseeable and uncontrollable events.”

“屈从于战争狂热的政治家必须意识到，一旦信号发出，他便不再是政策的主宰，而是不可预见、不可控制事件的奴隶。”