But there are important differences between the Masterpiece Cakeshop case and the legal dispute over Trump’s travel ban, said Ira C. Lupu, an expert on religion and constitutional law at George Washington University in the nation’s capital.

“It is a double standard,” Lupu said, “and it is justified to a point.”

The travel ban case was primarily about the separation of powers, Lupu said. That is, whether one branch of the federal government, the Supreme Court, could constrain or even overrule another branch, the executive.

The case is also about national security and how our country relates to foreign ones. In a footnote, Chief Justice John Roberts suggests it may not be appropriate to apply the Constitution’s establishment clause, which prohibits the government from favoring a particular religion, to national security issues and foreign affairs.