On April 10, 2018, President Trump signed Proclamation 9645, establishing a framework for enhanced vetting processes at U.S. ports of entry targeting individuals deemed potential security or public safety threats. The proclamation directed the Department of Homeland Security to implement heightened screening protocols, including intensified background checks, document verification, and security procedures for all prospective entrants to the United States. This represented a formal codification of vetting mechanisms that would remain in effect across subsequent administrations and successive policy iterations.

The proclamation directly affected individuals seeking lawful entry to the United States, including visa applicants, refugees, asylum seekers, and travelers. The enhanced vetting framework created extended processing times and increased documentary burdens for foreign nationals attempting to enter through legitimate channels. Families faced prolonged separation during adjudication periods, while visa interview wait times extended substantially in certain countries and consular posts, effectively narrowing the practical accessibility of legal entry pathways.

The 2018 proclamation functioned as a foundational instrument for the broader immigration enforcement apparatus that expanded significantly by 2026. Subsequent actions escalated the vetting framework into more aggressive detention and exclusion policies. The Trump administration's closure of the Office of the Immigration Detention Ombudsman in May 2026 removed oversight mechanisms that might have documented adverse effects of extended vetting holds. Simultaneously, updated green card denial policies based on political speech assessment created compound barriers where individuals cleared through enhanced vetting could still face exclusion based on their expressive conduct, effectively weaponizing the vetting determination process beyond traditional security considerations.

The 2018 proclamation itself faced no immediate successful legal challenge, though it operated within a contested legal landscape. By 2026, courts had begun challenging correlated detention policies, with the Second Circuit rejecting indefinite detention without bond consideration. However, the foundational vetting authority established in 2018 remained largely insulated from judicial review, operating as the baseline mechanism authorizing the downstream detention and deprivation policies that courts later scrutinized.