惠特尼表示，根据当前草案，沃尔克法则“将彻底改变游戏规则”。比如，除了禁止自营交易，银行也不能再持有证券，以满足客户可能购买的不时之需；这个过程必须是客户先表明购买意愿。“我不能事先准备好牛奶，都放在牛奶盒里。得等顾客下单后，我才能出去着手物色奶牛，”惠特尼称。这“会极大地放缓业务速度”。

    其他新条例亦如此，特别是监管机构将要实施的、更高的资本金要求。多德-弗兰克法案催生的全新监管机构效果如何，目前仍未可知。美国金融稳定监管委员会（The Financial Stability Oversight Council）刚刚起步。美国消费者金融保护局（Consumer Financial Protection Bureau）的局长人选尚空缺。这些机构以及数百条需起草的新条例，将收缩华尔街的触及范围，放缓其业务速度。这就是监管改革的目的。

    在这样的环境里，华尔街的商业模式是什么？人们不断听到的字眼是“回到未来”——利润将主要来源于承销费、并购咨询费和投资管理费，而不是高杠杆比率的自营交易。它对于高净值个人而言是个好消息：这些人会感受到更多的关爱。“每家华尔街公司都在盯着财富管理，”其中一家公司的前高管表示。这也难怪，这项业务高回报、低波动。但要拓展财富管理业务很难，因为这些有钱的客户更看重顾问个人，而不是这些顾问所代表的公司。然而，招聘和建立一支顶级顾问团队需要时间。

    华尔街面临的一个更大的挑战是华尔街已不再是金融世界的中心。2005年，全球市值最高的十家银行里有5家是美国银行，前五中就占据了4家，高居榜首的是花旗集团（Citigroup），其次是美国银行（Bank of America），前十中绝无中资银行身影。如今，前十大银行中已经有4家是中资银行，拔得头筹的是中国工商银行（Industrial & Commercial Bank of China），其次是中国建设银行（China Construction Bank）。只有4家是美国银行，其中市值最大的富国银行（Wells Fargo）也仅居第四。全球私募股权投资巨头——凯雷集团（Carlyle Group）的董事总经理戴维·鲁宾斯坦提出了一个关键的问题：“当今的美国仍能主导全球金融市场吗？1960年美国占全球GDP总量为46%，现在为21%。我们仍能独霸全球投资银行业吗？”

    答案显然是否定的。推而广之，华尔街必须进行痛苦的变革。几年前盈利能力还让人艳羡不已的华尔街大公司如今连资本成本也赚不回来。它们正在陨落，而其近期前景更是毋庸置疑：回报率和利润将进一步下降。这些公司必须瘦身，削减费用，降低薪资。昔日的辉煌已经不再。

    但是别着急。华尔街的光辉岁月似乎是十年一个周期，就像时钟一样精准。20世纪70年代末由于长达十年的市场停滞，华尔街也曾暂别光荣岁月；80年代末时也一样，当时收购和管理层并购（LBO）都出现了降温；90年代末，伴随着网络泡沫破灭；如今则是因为次贷危机。然而，每一次，华尔街都以无人能预见的新方式卷土重来。

    这个规律让华尔街仍然心存希望。但是对于巴尼·弗兰克和他大力协助打造的大批新监管机构来说，这一点却令人担忧。

    As currently drafted, the Volcker Rule is "a complete game changer," says Whitney. Beyond the ban on proprietary trading, for example, banks may no longer hold securities in inventory on the chance that a customer might want them; a customer must first state an intention to buy them. "I can't have anything in the dairy case. When you order, I've got to go out and find the cow," says Whitney. And that "slows the business down dramatically."

    So will other new rules, especially the higher capital requirements that regulators are imposing. The effects of entirely new regulatory bodies created by Dodd-Frank are still mostly unknown. The Financial Stability Oversight Council is just getting started. The Consumer Financial Protection Bureau doesn't yet have a director. They, and the hundreds of new rules still to be written, will shorten Wall Street's reach and hinder its speed. That's what they're meant to do.

    What is Wall Street's business model in a world like that? The phrase you keep hearing is "back to the future" -- making money on fees for underwriting, M&A advice, and investment management rather than on highly leveraged proprietary trading. Good news for high-net-worth individuals: You'll be feeling lots more love. "Each of these firms is looking at wealth management," says a former top executive at one of them. No wonder: It's a high-return, low-volatility business. But building it is hard because those well-off clients are far more attached to their advisers than to the firms those advisers represent. Recruiting and developing an army of top-quality advisers take time.

    A bigger challenge for Wall Street is that its turf is no longer the center of the financial universe. In 2005, five of the world's 10 most valuable banks were American, including four of the top five, led by No. 1 Citigroup (C) and No. 2 Bank of America (BAC); none of the top 10 were Chinese. Today four of the top 10 are Chinese, led by No. 1 Industrial & Commercial Bank of China and No. 2 China Construction Bank. Only four are American, the most valuable of which, Wells Fargo (WFC), is No. 4. David Rubenstein, managing director of the giant Carlyle Group private equity firm, poses the key questions: "Is the U.S. still able to dominate global financial markets? We were 46% of the world's GDP in 1960. Now we're 21%. Can we still have virtually 100% of the world's investment banks?"

    The answer -- no -- is obvious. More broadly, Wall Street has to change in painful ways. The major firms, gloriously profitable just a few years ago, are not earning their cost of capital. They're failing, and everyone seems to agree on their near-term future: lower returns and lower profits. The firms have to get smaller, cut expenses, live less large, pay people less. The glory days are over.

    But hold on. Wall Street's glory days are over every 10 years, like clockwork. They were over at the end of the '70s, after a decade of market stagnation; again at the end of the '80s, when takeovers and LBOs faded; at the end of the '90s, with the dotcom bust; and now with the subprime disaster. Every time, Wall Street comes back in new ways that no one imagined.

    That pattern is hopeful for the firms. For Barney Frank and the legions of new regulators he helped to create, it's worrisome.