Those of us who write about foreign policy--or any topic, for that matter--yearn for the day when the president of the United States lauds our work. That is exactly what happened in January to Robert Kagan, a fellow at the Brookings Institution and an adviser to the Romney campaign. Just before delivering the State of the Union address, President Obama told a collection of news anchors that his thinking had been influenced by Kagan's recent cover essay in The New Republic, "Not Fade Away: The Myth of American Decline." It is not often that a president running for reelection praises his chief rival's counselor.
Kagan's article, which draws on his new book, The World America Made, contests the emerging consensus in foreign-policy circles that American primacy is eroding thanks to the shift in global power from the West to the "rising rest." China and other nations are steadily ascending, this view holds, while the United States and its allies are stuck in an economic rut. The long era of Western hegemony seems to be coming to an end.
Kagan begs to differ. He contends that U.S. primacy is undiminished and that Americans, as long as they set their minds to it, are poised to sit atop the global pecking order for the indefinite future. The nation's share of global economic output has been holding steady, and its military strength "remains unmatched." China, India, Brazil, Turkey, and other emerging powers are certainly on the move, Kagan acknowledges, but he maintains that only China will compromise U.S. interests. The others will either align with the United States or remain on the geopolitical sidelines. The biggest threat to U.S. hegemony is that "Americans may convince themselves that decline is indeed inevitable"--and choose to let it happen. Kagan wants to persuade them otherwise and to call forth the political energies needed to ensure that the United States remains "the world's predominant power."
Although it sounds reassuring, Kagan's argument is, broadly, wrong. It's true that economic strength and military superiority will preserve U.S. influence over global affairs for decades to come, but power is undeniably flowing away from the West to developing nations. If history is any guide, the arrival of a world in which power is more widely distributed will mean a new round of jockeying for position and primacy. While it still enjoys the top rank, the United States should do its best to ensure that this transition occurs peacefully and productively. The worst thing to do is to pretend it's not happening.
By overselling the durability of U.S. primacy, Kagan's analysis breeds an illusory strategic complacency: There is no need to debate the management of change when one denies it is taking place. Even worse, the neoconservative brain trust to which Kagan belongs chronically overestimates U.S. power and its ability to shape the world. The last time that like-minded thinkers ran the show--George W. Bush's first term as president--they did much more to undermine American strength than to bolster it. Neoconservative thinking produced an assertive unilateralism that set the rest of the world on edge; led to an unnecessary and debilitating war in Iraq, the main results of which have been sectarian violence and regional instability; and encouraged fiscal profligacy that continues to threaten American solvency. Kagan would have us fritter away the nation's resources in pursuit of a hollow hegemony.
Instead, it is time for thrift: Washington should husband its many strengths, be more sparing with military force, and rely on judicious diplomacy to tame the onset of a multipolar world.
The Clock is Running
American primacy is not as resilient as Kagan thinks. His most serious error is his argument that Americans need not worry about the ascent of new powers because only Europe and Japan are losing ground to them; the United States is keeping pace. It's true that the U.S. share of global output has held at roughly 25 percent for several decades. It's also the case that "the rise of China, India, and other Asian nations ... has so far come almost entirely at the expense of Europe and Japan, which have had a declining share of the global economy." But this is not, as Kagan implies, good news for the United States.
The long run of Western hegemony has been the product of teamwork, not of America acting alone. Through the 19th century and up until World War II, Europe led the effort to spread liberal democracy and capitalism--and to guide Western nations to a position of global dominance. Not until the postwar era did the United States take over stewardship of the West. Pax Britannica set the stage for Pax Americana, and Washington inherited from its European allies a liberal international order that rested on solid commercial and strategic foundations. Moreover, America's many successes during the past 70 years would not have been possible without the power and purpose of Europe and Japan by its side. Whether defeating communism, liberalizing the global economy, combating nuclear proliferation, or delivering humanitarian assistance, Western allies formed a winning coalition that made effective action possible.
The collective strength of the West is, however, on the way down. During the Cold War, the Western allies often accounted for more than two-thirds of global output. Now they represent about half of output--and soon much less. As of 2010, four of the top five economies in the world were still from the developed world (the United States, Japan, Germany, and France). From the developing world, only China made the grade, coming in at No. 2. By 2050, according to Goldman Sachs, four of the top five economies will come from the developing world (China, India, Brazil, and Russia). Only the United States will make the cut; it will rank second, and its economy will be about half the size of China's. Moreover, the turnabout will be rapid: Goldman Sachs predicts that the collective economic output of the top four developing countries--Brazil, China, India, and Russia--will match that of the G-7 countries by 2032.
Kagan is right that the United States will hold its own amid this coming revolution. But he is certainly misguided to think that the relative decline of Europe and Japan won't matter. Their falling fortunes will compromise America's ability to maintain global sway. Indeed, Kagan seems to admit as much when he acknowledges, "Germany and Japan were and are close democratic allies, key pillars of the American world order."
Kagan is ready to gloss over the consequences of the West's diminishing clout because he thinks that most emerging nations will cast their lot with the United States rather than challenge American hegemony. "Only the growth of China's economy," he writes, "can be said to have implications for American power in the future." Kagan is confident that the rise of others--including Brazil, India, and Turkey--"is either irrelevant to America's strategic position or of benefit to it."
But Washington simply can't expect emerging powers other than China to line up on its side. History suggests that a more equal distribution of power will produce fluid alignments, not fixed alliances. During the late 19th century, for example, the onset of a multipolar Europe produced a continually shifting network of pacts. Large and small powers alike jockeyed for advantage in an uncertain environment. Only after imperial Germany's military buildup threatened to overturn the equilibrium did Europe's nations group into the competing alliances that ultimately faced off in World War I. As the 21st century unfolds, China is more likely than other emerging nations to threaten U.S. interests. But unless or until the rest of the world is forced to choose sides, most developing countries will keep their options open, not obediently follow America's lead.
Already, rising powers are showing that they'll chart their own courses. Turkey for decades oriented its statecraft westward, focusing almost exclusively on its ties to the United States and Europe. Now, Ankara looks primarily east and south, seeking to extend its sway throughout the Middle East. Its secular bent has given way to Islamist leanings; its traditionally close connection with Israel is on the rocks; and its relations with Washington, although steadier of late, have never recovered from the rift over the U.S. invasion of Iraq in 2003.
India is supposedly America's newest strategic partner. Relations have certainly improved since the 2005 agreement on civilian nuclear cooperation, and the two nations see eye to eye on checking China's regional intentions. But on many other fronts, Washington and New Delhi are miles apart. India frets, for instance, that the U.S. will give Pakistan too much sway in Afghanistan. On the most pressing national security issue of the day--Iran's nuclear program--India is more of a hindrance than a help, defying Washington's effort to isolate Iran through tighter economic sanctions. And the two democracies have long been at loggerheads over trade and market access.
Nations such as Turkey and India, which Kagan argues will be either geopolitically irrelevant or solid American supporters, are already pushing back against Washington. And they are doing so while the United States still wields a pronounced preponderance of power. Imagine how things will look when the playing field has truly leveled out.
Despite his faith that rising powers (save China) will be America's friends, Kagan at least recognizes that their ascent could come at America's expense. Will not the "increasing economic clout" of emerging powers, he asks, "cut into American power and influence?" He offers a few reasons not to worry, none of which satisfies.
For starters, he claims that the growing wealth of developing nations need not diminish U.S. sway because "there is no simple correlation between economic growth and international influence." He continues, "Just because a nation is an attractive investment opportunity does not mean it is a rising great power."
True enough. But one of the past's most indelible patterns is that rising nations eventually expect their influence to be commensurate with their power. The proposition that countries such as India and Brazil will sit quietly in the global shadows as they become economic titans flies in the face of history. Other than modern-day Germany and Japan--both of which have punched well below their weight due to constraints imposed on them after World War II--a country's geopolitical aspirations generally rise in step with its economic strength. During the 1890s, for instance, the United States tapped its industrial might to launch a blue-water navy, rapidly turning itself from an international lightweight into a world-class power. China is now in the midst of fashioning geopolitical aspirations that match its economic strength--as are other emerging powers. India is pouring resources into its navy; its fleet expansion includes 20 new warships and two aircraft carriers.
To support his thesis that emerging powers are not rising at the expense of U.S. influence, Kagan also argues that pushback against Washington is nothing new. He then cites numerous occasions, most of them during the Cold War, when adversaries and allies alike resisted U.S. pressure. The upshot is that other nations are no less compliant today than they used to be, and that the sporadic intransigence of emerging powers is par for the course.
But today's global landscape is new. By presuming that current circumstances are comparable with the Cold War, Kagan underestimates the centrifugal forces thwarting American influence. Bipolarity no longer constrains how far nations--even those aligned with Washington--will stray from the fold. And the United States no longer wields the economic influence that it once did. Its transition from creditor to debtor nation and from budget surpluses to massive deficits explains why it has been watching from the sidelines as its partners in Europe flirt with financial meltdown. The G-7, a grouping of like-minded democracies, used to oversee the global economy. Now that role is played by the G-20, a much more unwieldy group in which Washington has considerably less influence. And it is hardly business as usual when foreign countries lay claim to nearly 50 percent of publicly held U.S. government debt, with an emerging rival--China--holding about one-quarter of the American treasuries owned by foreigners.
Yes, U.S. leadership has always faced resistance, but the pushback grows in proportion to the diffusion of global power. China may prove to be America's most formidable competitor, but other emerging nations will also be finding their own orbits, not automatically aligning themselves with Washington. America's most reliable partners in the years ahead will remain its traditional allies, Europe and Japan. That's why it spells trouble for the United States that these allies are on the losing end of the ongoing redistribution of global power.
The Wrong Lesson
Finally, Kagan's timing is off. He is right that power shifts over decades, not years. But he underestimates the speed at which substantial changes can occur. He notes, for example, "The United States today is not remotely like Britain circa 1900, when that empire's relative decline began to become apparent. It is more like Britain circa 1870, when the empire was at the height of its power." After two draining wars, an economic crisis, and deepening defense cuts, this assertion seems doubtful. But let's assume that the United States is indeed "at the height of its power," comparable with Britain circa 1870.
In 1870, British hegemony rested on a combination of economic and naval supremacy that looked indefinitely durable. Two short decades later, however, that picture had completely changed. The simultaneous rise of the United States, Germany, and Japan altered the distribution of power, forcing Britain to revamp its grand strategy. Pax Britannica may have technically lasted until World War I, but London saw the writing on the wall much earlier--which is precisely why it was able to adjust its strategy by downsizing imperial commitments and countering Germany's rise.
In 1896, Britain began courting the United States and soon backed down on a number of disputes in order to advance Anglo-American amity. The British adopted a similar approach in the Pacific, fashioning a naval alliance with Japan in 1902. In both cases, London used diplomacy to clear the way for retrenchment--and it worked. Rapprochement with Washington and Tokyo freed up the fleet, enabling the Royal Navy to concentrate its battleships closer to home as the Anglo-German rivalry heated up.
It was precisely because Britain, while still enjoying preponderant strength, looked over the horizon that it was able to successfully adapt its grand strategy to a changing distribution of power. Just like Britain in 1870, the United States probably has another two decades before it finds itself in a truly multipolar world. But due to globalization and the spread of new manufacturing and information technologies, global power is shifting far more rapidly today than it did in the 19th century.
Now is the time for Washington to focus on managing the transition to a new geopolitical landscape. As the British experience makes clear, effective strategic adjustment means getting ahead of the curve. The alternative is to wait until it is too late--precisely what London did during the 1930s, with disastrous consequences for Britain and Europe. Despite the mounting threat posed by Nazi Germany, Britain clung to its overseas empire and postponed rearmament. After living in denial for the better part of a decade, it finally began to prepare for war in 1939, but by then it was way too late to stop the Nazi war machine.
Even Kagan seems to recognize that comparing the United States to Britain in 1870 may do his argument more harm than good. "Whether the United States begins to decline over the next two decades or not for another two centuries," he writes, "will matter a great deal, both to Americans and to the nature of the world they live in." The suggestion here is that the United States, as long as it marshals the willpower and makes the right choices, could still have a good 200 years of hegemony ahead of it. But two decades--more in line with the British analogy--is probably the better guess. It strains credibility to propose that, even as globalization speeds growth among developing nations, a country with less than 5 percent of the world's population will run the show for two more centuries.
Whether American primacy lasts another 20 years or another 200, Kagan's paramount worry is that Americans will commit "preemptive superpower suicide out of a misplaced fear of their own declining power." In fact, the greater danger is that the United States could head into an era of global change with its eyes tightly shut--in denial of the tectonic redistribution of power that is remaking the globe. The United States will remain one of the world's leading powers for the balance of the 21st century, but it must recognize the waning of the West's primacy and work to shepherd the transition to a world it no longer dominates. Pretending otherwise is the real "preemptive superpower suicide."
西方的衰落：为什么美国必须为主导地位的终结做好准备
我们这些为外交政策———或者任何相关主题———撰文立著的人渴望有朝一日美国总统会称赞我们的工作。今年1月份，布鲁金斯学会研究员、罗姆尼竞选班子顾问罗伯特卡根就碰上了这等好事。奥巴马总统在发表国情咨文之前，对一批新闻媒体人说，他的思想受到卡根最近在《新共和》杂志上发表的封面文章《不会消逝：美国衰落的神话》的影响。竞选连任的总统称赞主要对手的顾问，实属罕见。
卡根的这篇文章是其新书《美国缔造的世界》的摘要。这篇文章向外交圈中新达成的一致发起挑战。这种一致就是：由于全球实力从西方转向“日益崛起的其余地区”，美国的首要地位遭到侵蚀。这一观点认为，中国和其他国家正稳定上升，而美国及其盟友陷入经济困境，西方长期称霸的时代似乎走到了尽头。
卡根并不认同这一观点。他认为，美国的首要地位并未衰减，美国人只要下定决心，就能够在未来稳坐全球排名顶端。这个国家在全球经济总量中的比重保持稳定，其军事实力“仍然无可匹敌”。卡根承认，中国、印度、巴西、土耳其及其他新兴大国当然呈上升趋势，但他坚持认为，只有中国会危害到美国的利益。其他国家要么与美国结盟，要么仍然处于地缘政治边缘。对美国霸权构成最大威胁的是，“美国人可能自以为衰退实际上是无可避免的”，并且选择听之任之。卡根期望说服他们不要这么做，想要唤起要确保美国仍是“主导世界的力量”所必需的政治能量。
虽然听起来令人宽慰，但卡根的论点广泛而言是错误的。的确，经济实力和军事优势将在今后几十年使美国能维持对全球事务的影响力，但实力正无可置疑地从西方流向发展中国家。如果以史为鉴，实力更广泛分配的新世界的到来将意味着新一轮地位和主导力量的争夺战。美国虽然仍然享有顶端位置，但应竭尽所能确保这一过渡和平且富有成效（the United States should do its best to ensure that this transition occurs peacefully and productively）。最糟糕的事情莫过于假装没这回事。
通过过分吹嘘美国主导地位的耐久性，卡根的分析产生了虚无缥缈的战略自满（ an illusory strategic complacency）：如果否认正在发生变化，何谈应变管理。更糟糕的是，卡根所属的新保守主义智囊团习惯性高估美国的实力及其塑造世界的能力。这些志趣相投的思想家上一次操控全局是在乔治.W布什第一任总统任期的时候。当时，他们的所作所为与其说是增大了美国的实力，还不如说削弱了美国的实力。新保守主义思想产生了耀武扬威的单边主义，令世界其他地方紧张不安；导致没有必要、大伤元气的伊拉克战争，这场战争的主要后果就是宗派暴力和地区动荡；纵容财政挥霍，继续危及美国的偿债能力。卡根会让我们为了追求空洞的霸权而逐步消耗这个国家的资源。
相反，该节俭度日了：华盛顿应该节约使用许多实力，更加珍惜军事力量，依赖明智的外交活动来从一开始驯服一个多极世界。
时间在流逝
美国的主导地位并不像卡根所想的那样具有弹性。他的最严重错误就是，他认为，美国人无需担心新大国的上升，因为只有欧洲和日本才会输掉地盘，美国正在与这些新兴大国齐头并进。的确，美国在全球产出中的比重几十年来保持在25％左右。同样，“中国、印度以及其他亚洲国家的崛起……迄今完全是以欧洲和日本为代价，欧日在全球中的比重日益下降”。但对美国来说，这并非像卡根所暗指的那样是个好消息。
西方长期称霸是团队合作的产物，而不是美国单枪匹马奋战的结果（The long run of Western hegemony has been the product of teamwork, not of America acting alone）
。在整个19世纪以及一直到第二次世界大战之前，欧洲带头传播自由民主制度和资本主义———指引西方国家在全球占据主导地位。直到战后，美国才接过舵盘。英国治下的和平为美国治下的和平创造了条件，华盛顿从其欧洲盟友那里继承了依靠稳固商业和战略根基的自由国际秩序。此外，如果没有欧洲和日本的支持，美国在过去70年的成就有许多是不可能取得的。无论是击败共产主义、解放全球经济、遏制核扩散，还是提供人道主义援助，西方盟友组成了胜利联盟，使得行动尽可能行之有效。
然而，西方的集体实力正在下降。在冷战期间，西方盟友在全球产出中的比重通常超过2/3。而今，它们仅占一半左右———很快会少得更多。截至2010年，世界前5个经济体中有4个仍然来自发达世界（美国、日本、德国和法国）。在发展中世界，只有中国合乎标准，跻身第二。据高盛公司预测，到了2050年，头5个经济体中有4个将来自发展中世界（中国、印度、巴西和俄罗斯）。只有美国仍然达到标准；它将排在第二，其经济规模将仅是中国的一半。此外，转变将会十分迅速：高盛预言，到了2032年，前4个发展中国家———巴西、中国、印度和俄罗斯———的集体经济产出将与七国集团旗鼓相当。
卡根称美国将在即将到来的革命期间保持自我，这是对的。但他当然受到了误导，以为欧洲和日本的相对衰落无关紧要。它们的财富减少将削弱美国维持全球支配地位的能力。实际上，卡根似乎承认，“德国和日本过去是，现在也是美国的亲密民主盟友，是美国世界秩序的重要支柱。”卡根准备掩饰西方影响力下降的后果，因为他认为，大多数新兴国家将与美国休戚与共，而不是挑战美国的霸权。他写道：“只有中国的经济增长据说会对美国未来的实力产生影响。”卡根相信，其他国家的崛起———包括巴西、印度和土耳其———“要么与美国的战略地位无关，要么对其有利”。
但是，华盛顿根本无法指望除中国以外的新兴大国会与其处在同一条阵线。历史表明，实力的更平等分配会带来流动性结盟，而不是固定联盟（ a more equal distribution of power will produce fluid alignments, not fixed alliances. ）。例如，在19世纪末期，多极欧洲的出现带来了不断发生变化的条约网络。在不确定的环境下，大小强权国家同样在争夺优势地位。只有在帝国主义德国的军事集结大有可能打破均衡之后，欧洲国家才结成互相竞争的联盟，并最终在一战中形成对阵。随着21世纪拉开帷幕，中国比其他新兴国家更有可能威胁到美国的利益。但除非或者直到世界上其他地方被迫选择阵营，否则大多数发展中国家将保留选择余地，而不是顺从地服从美国的指挥（most developing countries will keep their options open, not obediently follow America's lead）。
崛起大国已经展示出它们将制订自己的路线。几十年来，土耳其一直向西看，几乎仅仅关注与美国和欧洲的关系。但现在，安卡拉主要向东和向南看，谋求将其影响力伸展至中东各地。它的世俗倾向已经让位于伊斯兰主义倾向；其历来与以色列的密切联系现在岌岌可危；它与华盛顿的关系虽然近来稳定一些，但美国2003年入侵伊拉克之后土美两国之间出现的裂痕从未得以弥合。
印度本应是美国最新的战略伙伴。自2005年就民用核合作达成协议以来，两国之间的关系改善了，并且双方在遏制中国的地区意图方面看法一致。但在其他许多方面，华盛顿和新德里相去甚远。例如，印度担心美国在阿富汗赋予巴基斯坦太多的影响力。在当今最迫在眉睫的国家安全问题（伊朗核计划）上，印度与其说是提供帮助，不如说是设置障碍。印度抵制华盛顿通过加强经济制裁孤立伊朗的努力。美印这两个民主国家长期以来在贸易和市场准入的问题上意见不合。
卡根认为，诸如土耳其和印度等国要么在地缘政治上无关，要么是美国的坚定支持者，但它们也已经开始抵制华盛顿，这还是在美国仍然拥有明显实力优势的时候。想象一下，当比赛场上实力势均力敌之时，事情会是什么样的吧。
虽然卡根相信崛起大国（除中国之外）将是美国的朋友，但他至少承认，它们的上升可能是以美国的上升为代价。他问道，新兴大国“日益增大的经济影响力”会否“削弱美国的实力和影响力”？他提出了几个无需担心的理由，但没有一个理由令人满意。
首先，他声称，发展中国家日益增大的财富不一定会削弱美国的影响力，因为“经济增长与国际影响力之间没有关联”。他接着说：“某个国家有吸引人的投资机会并不意味着它是个崛起的大国。”
没错。但是过去最难以磨灭的其中一个模式是，崛起国家最终希望它们的影响力能够与其实力相称。诸如印度和巴西等国在变成经济巨头时只会悄悄地坐在全球阴影里，这一说法违背了历史。不同于当代的德国和日本（二战后它们受到的限制令其影响力大打折扣），一个国家的地缘政治雄心总体而言与其经济实力同步上升。例如，在19世纪90年代期间，美国利用其工业力量打造“蓝海海军”，迅速将自身从无足轻重的国家变成世界一流强国。中国现在处于塑造与其经济实力相称的地缘政治雄心的时期，正如其他新兴大国一样。印度正将资源投入到海军之中，其舰队扩张包括20艘新军舰和两艘航母。
为了支持他提出的新兴大国的崛起不会以美国的影响力为代价这一理论，卡根还争辩说，美国受到推挡并不是新鲜事。他然后举出无数个例子，大多数发生在冷战期间。当时对手和盟友同样都在抵制美国的压力。结局是，这些国家的态度跟过去差不多，新兴国家时不时采取不妥协的立场是意料之中的。
但是，全球景观如今已经焕然一新。通过假定目前的环境堪比冷战时期，卡根低估了破坏美国影响力的离心力。两极不再限制各国———即使是那些与华盛顿结盟的国家———到底走多远。美国不再拥有它过去拥有的经济影响力。它从债权方变成到债务方，从预算盈余变成严重赤字，这就解释了为什么在欧洲伙伴遭遇金融危机时，它只能袖手旁观。由志同道合民主国家组织的七国集团过去常常共同监督全球经济。而今，这个角色由二十国集团来扮演。这是个大得多也笨拙得多的组织，华盛顿在其中的影响力也小得多。在外国宣称持有一半公开发行的美国政府债券，而外国人持有的美国国库券中又有大约1/4在新兴对手———中国———的手上时，根本不会一切如常。
是的，美国的领导权向来遭遇抵制，但抵制随着全球实力的分散而增大。中国或许可能证明是美国最强大的竞争对手，但其他新兴国家也将发现它们自己的轨道，不会自动与华盛顿结盟。在今后几年，美国最可靠的伙伴仍然是其传统盟友、欧洲和日本。正因如此，如果这些盟友在正在进行的全球实力分配中成为输家，就意味着美国遇到了麻烦。
反面教训最后，卡根的时间算得不对。他说，实力几十年都在发生变化，而不是这几年才发生变化。他是对的。但是，他低估了实质性变化发生的速度。例如，他指出，“美国今天跟1900年前后的英国没有太多相似之处，当时英帝国的相对衰落开始变得明显。美国现在更像1870年前后的英国，当时英帝国正处于实力的巅峰。”在美国经过两场耗费大量资源的战争、一场经济危机、大规模削减防御开支之后，这一断言似乎并不可信。但就让我们假设，美国事实上正处于“实力的巅峰”，可与1870年前后的英国相比。
1870年，英国的霸权依靠的是看上去无限期存在的经济和海上优势。然而，短短20年之后，情况就完全发生了变化。美国、德国和日本的同时崛起改变了实力分配，迫使英国修改其宏图伟略。严格来说，英国治下的和平或许持续到第一次世界大战，但伦敦更早些时候就看到了明摆的事情———正因如此，它才能够调整其战略，降低帝国主义承诺、一心抗衡德国的崛起。
1896年，英国开始讨好美国，很快就在一些争端方面放低了姿态，以便推进英美亲善关系。英国在太平洋采取了类似的做法，与日本在1902年建立了海上联盟。在这两种情形下，伦敦都利用外交为紧缩扫清了道路———它成功了。与华盛顿和东京的和解使英国舰队能够分身出来，从而使英国皇家海军在英德对立加剧的时候，把军舰集中在更靠近国内的地方。
正是因为英国在仍然享有优势实力的情况下打开眼界，它才能够成功地将其宏大战略适应发生变化的实力分配。就像1870年的英国一样，美国或许再过20年就会发现自己身处一个真正的多极世界。但由于全球化、新制造业及信息技术的传播，全球实力的变化速度远远大于19世纪。
现在，华盛顿该把注意力集中在向新的地缘政治图景过渡上面了。正如英国的经历所明示的那样，有效的战略调整意味着能够未雨绸缪。相反，就只能等到为时已晚，正如伦敦在20世纪30年代那样，当时这一做法给英国和欧洲带来了灾难性后果。虽然纳粹德国构成的威胁越来越严重，英国还在死守其海外帝国不放，迟迟没有重整军备。在这10年的大部分时间里，英国都拒绝接受现实，最后到了1939年才开始备战，但到了那时要制止纳粹的战争机器已为时太晚。
就连卡根似乎都认识到，把美国比作1870年的英国对他的论点来说弊大于利。他写道：“无论美国是在今后20年开始衰落，还是再过200年都不会衰落，都对美国人以及他们生活的世界来说有着重大干系。”这话的含义是，美国只要能够调集意志力，做出正确的选择，就能够安然再享200年的霸权。但是，20年———与英国的例子更一致———或许才是更靠谱的估计。在今后200年，在发展中国家的全球化速度增大的时候，一个人口不到全球总人口5％的国家仍然会掌控大局，这一说法实在令人难以相信。
无论美国的主导地位是持续20年还是200年，卡根最主要的担心是，美国人“出于对臆想中的衰落的恐惧，很可能贸然采取相应对策，把一个超级大国引上自杀之路”。事实上，更大的危险是，美国可能双眼紧闭地撞向全球变化的时代———拒绝接受实力重新分配正重新塑造全球的现实。在21世纪，美国仍将是世界上最主要的大国之一，但它必须承认西方的主导地位正在减退，并且致力于引领西方过渡到一个它不再占支配地位的世界。假装这种事不会发生才是真正的“超级大国自杀行为”（Pretending otherwise is the real "preemptive superpower suicide.）。（洪漫译）
U.S. Foreign
Policy and the Geopolitics of the Twenty-first Century
作者：Charles Kupchan
