The Trump administration won an important victory and America’s national security was strengthened Tuesday when the Supreme Court upheld President Trump’s travel ban that suspended the entry into the U.S. of foreigners from countries that are state sponsors of terrorism or pose other national security threats.

The 5-4 decision also demonstrates just how important the current conservative majority is on the Supreme Court.

Chief Justice John Roberts wrote the majority opinion for the high court, finding that the president lawfully exercised the broad discretion granted to him by Congress in federal immigration law to suspend the entry of foreigners from certain countries.

As the court explained, the president’s travel ban proclamation of September 2017 was intended to improve the vetting procedures that America uses for foreign nationals traveling to the U.S., to ensure we are identifying those who pose a national security threat.

The proclamation suspended entry into the U.S. from eight nations – Chad, Iran, Iraq, Libya, North Korea, Syria, Venezuela, and Yemen – but only after the Department of Homeland Security, in consultation with the State Department, developed an information and risk assessment baseline that was applied to all nations in the world. Chad was later dropped from the list.

The Supreme Court said President Trump’s proclamation falls “well within” the federal law’s comprehensive delegation of authority to the president.

The president must find the entry of the foreigners to be “detrimental to the interests of the United States.” There is no question that President Trump fulfilled that requirement here. In fact, his proclamation is more detailed that any order by prior presidents issued under this federal law.

President Trump wasn’t required to set a date when the travel suspension would end, and neither the legislative history of the law nor historical practice justified departing from the clear text of the statute.

The plaintiffs in this case, which include the state of Hawaii and the Muslim Association of Hawaii, claimed that supposedly anti-Muslim statements made by Donald Trump during his presidential campaign and after he became president showed that his proclamation was the result of religious bias. But the Supreme Court majority didn’t buy that argument.

The high court pointed out that the proclamation was a presidential directive that is neutral on its face – that is, the proclamation shows no hostility to any religion, and it deals with a matter within the core of executive responsibility.

The admission and exclusion of foreign nationals is a fundamental sovereign power that is exercised by the government’s political departments, Congress and the president, and it is largely immune from judicial control.

The Supreme Court emphasized that the entry restrictions are limited to countries that were previously designated by Congress or prior administrations as posing national security risks.

And the court pointed out that the proclamation was only issued by President Trump after a worldwide review process undertaken by multiple Cabinet officials and their agencies.

The Supreme Court wasn’t willing to substitute its own judgment on national security issues for that of the president and the executive branch.

Finally, Chief Justice Roberts was obviously annoyed by those, including the liberal justices dissenting in this case, who have tried to compare the travel ban to the presidential order issued by President Franklin Roosevelt that interned Japanese Americans during World War II.

The internment order has “nothing to do with this case,” Roberts said. He added that “it is wholly inapt to liken that morally repugnant order to a facially neutral policy denying certain foreign nationals the privilege of admission” to the United States. The president cited a “sufficient national security justification” for this order and that is the end of the matter.

There are obviously compelling reasons to worry about the entry of foreign nationals from state sponsors of terrorism like Iran. The public, the administration, and a majority of the Supreme Court all understand that. What is amazing is that four members of the court do not.