This paper commemorates the influence of Arjen Y. Hoekstra on water footprint research of the United States. It is part of the Special Issue “In Memory of Prof. Arjen Y. Hoekstra”. Arjen Y. Hoekstra both inspired and enabled a community of scholars to work on understanding the water footprint of the United States. He did this by comprehensively establishing the terminology and methodology that serves as the foundation for water footprint research. His work on the water footprint of humanity at the global scale highlighted the key role of a few nations in the global water footprint of production, consumption, and virtual water trade. This research inspired water scholars to focus on the United States by highlighting its key role amongst world nations. Importantly, he enabled the research of many others by making water footprint estimates freely available. We review the state of the literature on water footprints of the United States, including its water footprint of production, consumption, and virtual water flows. Additionally, we highlight metrics that have been developed to assess the vulnerability, resiliency, sustainability, and equity of sub-national water footprints and domestic virtual water flows. We highlight opportunities for future research.

中文翻译：

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美国的水足迹

本文纪念 Arjen Y. Hoekstra 对美国水足迹研究的影响。它是“纪念 Arjen Y. Hoekstra 教授”特刊的一部分。Arjen Y. Hoekstra 既启发了学者们，又促使他们致力于了解美国的水足迹。他通过全面建立作为水足迹研究基础的术语和方法来做到这一点。他关于全球范围内人类水足迹的工作突出了少数国家在生产、消费和虚拟水贸易的全球水足迹中的关键作用。这项研究通过强调美国在世界各国中的关键作用，激发了水资源学者将注意力集中在美国。重要的，他通过免费提供水足迹估计值，使许多其他人的研究成为可能。我们回顾了美国水足迹的文献状况，包括其生产、消费和虚拟水流的水足迹。此外，我们重点介绍了为评估次国家级水足迹和国内虚拟水流的脆弱性、弹性、可持续性和公平性而制定的指标。我们强调未来研究的机会。次国家水足迹和国内虚拟水流量的公平性。我们强调未来研究的机会。次国家水足迹和国内虚拟水流量的公平性。我们强调未来研究的机会。