An alien 'arrives in the United States' when he or she presents at a U.S. port of entry and seeks admission, regardless of physical crossing.

1) The question: Does an alien seeking admission at a land border port of entry 'arrive in the United States' under 8 U.S.C. §§1158(a)(1) and 1225(a)(1) before physically crossing the borderline? 2) Relevant constitutional text: Article I, Section 8, Clause 3 gives Congress power to regulate commerce with foreign nations, which includes the exclusive power to set the terms of admission. The Tenth Amendment reserves to the states powers not delegated, but immigration is inherently federal. The Bill of Rights (Due Process Clause) applies to all persons within U.S. jurisdiction, which has historically included ports of entry. 3) Ratification-era understanding: At the founding, 'arriving in' a country meant reaching its borders or ports, as the act of entry was consummated by presentation at the port. The 1790 Naturalization Act used 'arriving in the United States' to mean landing at a port. Similarly, early immigration statutes (e.g., 1875 Page Act) treated presentation at a port as 'arrival.' The phrase 'arrives in the United States' thus included the moment a vessel or person reached the port and sought entry. 4) Holding: The INA's use of 'arrives in the United States' in Sections 1158(a)(1) and 1225(a)(1) requires inspection and the opportunity to apply for asylum when an alien presents himself or herself at a designated port of entry and makes contact with a U.S. immigration officer. This reading gives independent meaning to both 'arrives in' and 'physically present'—the former covers aliens at the border seeking admission, the latter covers aliens already inside. The government retains the authority to temporarily delay inspection through reasonable metering measures when port capacity is exceeded, but such measures must not permanently deny access and must be applied in a non-arbitrary manner consistent with the Due Process Clause. 5) Downstream changes: The declaratory judgment of the district court is affirmed. The metering policy, as applied, was unlawful because it denied inspection altogether; however, the government may implement a metering system that provides a reasonable queue and guarantees timely processing. The Ninth Circuit's judgment is vacated and the case remanded for entry of a modified injunction consistent with this holding.