This article from “Constitutional Issues of Taxation.pdf” examines the constitutional limits of federal taxation in the United States. It explains the distinction between direct and indirect taxes, emphasizing the importance of apportionment for direct taxes and uniformity for indirect taxes. The article focuses heavily on the 16th Amendment and its impact on the interpretation of “income tax,” arguing that the amendment’s scope is narrower than generally understood. It further asserts that the current enforcement of income tax might unconstitutionally transform excise taxes into direct taxes, and discusses the implications for taxpayers. Finally, the article highlights the significance of distinguishing between “business” and “private affairs” to avoid unintended tax liabilities.