Fogel concludes that railroads were important but not "essential" to late 19th century growth in the U.S. in the sense that a possible alternative existed even if it was never tried.
福格尔总结道：铁路确实重要，但对于美国在19世纪晚期的增长而言绝非“不可或缺”（essential），我们应当清楚当时是存在替代品的可能性的——尽管我们从未尝试过。