Citizens of Chad now face travel restrictions to the United States, following a Sunday announcement by President Donald Trump that names eight countries on a new list of suspensions – but removes the previous restrictions against citizens of Sudan.

Chad, along with Libya and Somalia, are the three African nations on the list, which also includes Venezuela, North Korea, Syria, Yemen and Iran. In statements issued by the White House, the Trump administration explained that the new rules are based on compliance with U.S. security expectations evaluated in a number of countries, and reflect whether or not they’ve upgraded passport controls and other requirements.

“It is the President’s solemn duty to protect the American people and with this order, President Trump is exercising his authority to keep our people safe,” said U.S. Secretary of State Rex Tlllerson as the new rules were rolled out. The decisions include specific details about why countries are included, as was the case with Chad.

“Although it is an important partner, especially in the fight against terrorists, the government in Chad does not adequately share public-safety and terrorism-related information, and several terrorist groups are active within Chad or in the surrounding region, including elements of Boko Haram, ISIS-West Africa, and al-Qa’ida in the Islamic Maghreb,” the White House said. “Accordingly, the entry into the United States of nationals of Chad, as immigrants, and as nonimmigrants on business (B-1), tourist (B-2), and business/tourist (B-1/B-2) visas, is suspended.”

The new rules replace a controversial travel ban Trump announced immediately after taking office in January. That ban on travel from six nations, including Sudan, was revised following U.S. legal challenges and implementation problems, and was in force for a 90-day window that also expired on Sunday.

The old law was modified by the U.S. Supreme Court to ensure that it “could not be enforced against foreign nationals who have a credible claim of a bona fide relationship with a person or entity in the United States.” Travel to visit family, or for documented students and workers, remained protected under the Supreme Court’s temporary decision ahead of a full case hearing scheduled for this fall.

How the new travel ban works

The new list offers insight into why some countries are subject to the travel ban. For Libya, the White House and partnering agencies said Libya “faces significant challenges in sharing several types of information, including public-safety and terrorism-related information.” U.S. officials also cited significant inadequacies in identity management protocols, a lack of cooperation when Libyans are deported from the United States, and a “substantial terrorist presence within its territory.” Libyans are subject to the same visa type suspensions as Chadians.

Somalia is treated slightly differently. “Although it satisfies minimum U.S. information-sharing requirements, the government in Somalia still has significant identity-management deficiencies,” officials said. “It is recognized as a terrorist safe haven; remains a destination for individuals attempting to join terrorist groups that threaten the national security of the United States; and struggles to govern its territory and to limit terrorists’ freedom of movement, access to resources, and capacity to operate.”

That means all immigration for Somalis is suspended, and non-immigrants traveling to the U.S. will be subject to enhanced screening and vetting requirements.

The supporting argument for the new travel ban on North Korea was brief and blunt, which perhaps comes as no surprise given the hostility between Trump and Kim Jong-un, who in recent days has been mocked by the U.S. president with the “Rocket Man” moniker at the United Nations General Assembly and subsequently on social media.

“The government in North Korea does not cooperate with the United States Government in any respect and fails to satisfy all information-sharing requirements,” the White House document said. “Accordingly, the entry into the United States of nationals of North Korea as immigrants and nonimmigrants is suspended.”

Effective dates and assessment criteria

For citizens of those countries already under restrictions, the new rules take effect immediately. For nationals from Chad and the other two newly added nations, the U.S. entry ban begins at midnight on October 18.

The United States also released details on the vetting criteria used to make the decisions about the travel ban. They include identity management and passport integrity, including the use of biometric passports, and the timely and consistent reporting of lost or stolen passports to Interpol. Countries also were flagged for their failure to identify serious criminals, share data with the United States on known or suspected terrorists, and work closely with airlines and passenger ship lines to coordinate security.

For the nations themselves, the U.S. said it evaluates “whether the country is a known or potential terrorist safe haven,” what its visa requirements are, and whether or not the nation cooperates in accepting citizens deported from the U.S. and repatriated to their home countries. Earlier this month, the U.S. cut off some travel visas to Eritrea, Guinea and Sierra Leone because of their failure to accept citizens removed from the U.S.

For details about the new ruling, see this link.