There’s disturbing news out of Egypt — whose first post-Mubarak elected president is taking office — and it has worrisome implications for America.

In a fiery speech yesterday to hundreds of thousands in Cairo’s Tahrir Square, Mohammed Morsi took the oath of office — and vowed to obtain freedom for the blind sheik, Omar Abdel Rahman.

“I see banners for Omar Abdel Rahman’s family, and for prisoners arrested according to martial rulings and detainees from the beginning of the revolution,” said Morsi.

“It is my duty to make every effort, and I will beginning tomorrow to secure their release, among them Omar Abdel Rahman.”

AFP/Getty Images

Sheikh Omar Abdel Rahman

So much for those who insist that Morsi, the radical Muslim Brotherhood’s man, is a moderate — and that the group itself has moved beyond its Islamist origins.

After all, we’re talking about the same blind sheik now serving a life term in US prison for masterminding the 1993 World Trade Center bombing and plotting attacks on other New York landmarks.

The same blind sheik whose fatwa was cited by Osama bin Laden as religious justification for the 9/11 attacks.

The same blind sheik whose terrorist movement, Gamaa Ismaliya, elected members to Egypt’s new Islamist-dominated parliament.

Just last week, it was disclosed that one of those legislators had been granted a visa, in apparent defiance of US law, and been given a sit-down with Deputy National Security Adviser Denis McDonough.

And what did he do with this valuable face time?

Why, demand the release of Omar Abdel Rahman — the blind sheik.

All of which raises troubling questions.

The White House says it wants to work with Egypt’s new leadership. But that will bear fruit only if the Muslim Brotherhood has in fact discovered political moderation.

Was Morsi tossing a rhetorical bone to the screaming throngs in Cairo?

Does it make any difference?

The challenge was issued loudly and in public, and America’s response must be equally high profile.

President Obama and his secretary of state, Hillary Clinton, need to make it clear that they will not truck with terrorists — nor with their apologists in high places.