Abdul Moniem El-Ganayni, an American citizen, would have preferred to stay in his adopted country, but he returned to Egypt, the land of his birth, because he needs to make a living.

The 57-year-old physicist and prison chaplain left Egypt to study in Pittsburgh. He became a U.S. citizen 20 years ago. Since then, the co-founder of the Islamic Center of Pittsburgh has married and made his life here in our region.

Like a character in a Franz Kafka novel, Mr. El-Ganayni came under unspecified government suspicion a few years ago. Acting on "reliable information," the acting deputy energy secretary revoked Mr. El-Ganayni's security clearance last year, making it impossible for him to do his job at Bettis nuclear propulsion lab in West Mifflin.

Given the gravity of its action, one might have assumed the government would be eager to lay out its case publicly against Mr. El-Ganayni as a threat to national security, if only as a caution to others.

Because he has been a proud citizen for so long, Mr. El-Ganayni expected his country to explain why it felt compelled to deprive him of his livelihood. But the government's response was silence, prompting him to file a federal lawsuit seeking an independent review.

When the last count in his suit was dismissed in U.S. District Court in Pittsburgh last week, Mr. El-Ganayni kept his word to return to Egypt, where he accepted a job as a full professor of physics at a university. Mr. El-Ganayni's lawyers are appealing the court's decision in his absence.

The FBI and the Department of Energy continue to sit on the evidence they claim to have against the physicist. In doing so, the government has effectively smeared Mr. El-Ganayni and driven him out of the country without showing why he ostensibly poses a threat to the country.

This is a troubling episode that puts all Americans at risk. It will be up to the Obama administration to restore the expectation that due process is the right of every American -- including those born elsewhere.