The policy is set to be enforced starting Monday at 12:01 a.m. to prevent the chaotic scenes seen during the 2017 travel ban implementation.

The nations facing the ban include Afghanistan, Myanmar, Chad, the Republic of Congo, Equatorial Guinea, Eritrea, Haiti, Iran, Libya, Somalia, Sudan, and Yemen. Meanwhile, heightened restrictions will be imposed on visitors from Burundi, Cuba, Laos, Sierra Leone, Togo, Turkmenistan, and Venezuela.

Trump linked the new ban to the recent terror attack in Boulder, Colorado, attributing the necessity of the travel restrictions to the potential dangers posed by visa overstays. The attacker, a tourist from Egypt, overstayed his visa—a point Trump emphasized despite Egypt not being on the restricted list.

The rationale behind the inclusion of these countries, according to Trump, is based on their inadequate screening and vetting procedures, and in some cases, their refusal to take back their own citizens who overstay visas. This decision leans heavily on a report from the Department of Homeland Security highlighting countries with high visa overstay rates.

The inclusion of Afghanistan, in particular, has reignited controversy. The nation, which has been a significant source of resettled refugees to the U.S., is now part of the ban despite exceptions for those on Special Immigrant Visas—generally individuals who have worked closely with American forces. Advocates for Afghan refugees termed the decision as a betrayal of America's allies and values.

Haiti, which avoided restrictions during Trump's first term, is now listed due to high overstay rates and the ongoing violence and instability making enforcement of legal and security measures challenging. Similarly, the Iranian, Libyan, Sudanese, and Yemeni governments, all of which face varying degrees of internal strife and the presence of opposing factions, find their citizens restricted from entering the United States.

Various international aid and refugee organizations have voiced strong opposition to the new ban, condemning it as a policy aimed more at creating division rather than ensuring national security. Nonetheless, the Trump administration insists the measure is crucial for protecting the country's interests.