This article at the Washington Post says Islamic extremists have been able to operate freely in the US because the FBI is afraid of being politically incorrect: FBI Wary of Investigating Extremist Muslim Leaders.

Under the Foreign Intelligence Surveillance Act, the FBI has broad powers to wiretap or bug any site where foreign terrorist activity is suspected. But some law enforcement experts believe the FBI has hamstrung itself by excessive sensitivity about possible criticism because religious figures are involved.

“You can’t be in a struggle with a segment of a religious movement and not pursue them as you would any other suspected criminal,” said Phillip B. Heymann, a professor of criminal law at Harvard Law School.

It’s easy to see why extremists think the US is corrupt and weak, when the FBI—an agency that is supposed to protect US citizens—won’t even investigate known terrorists because it’s afraid of looking bad. So the FBI let this happen instead:

One current FBI interest is in Rahman’s followers — the network of imams and mosques he presided over and visited in the United States. The bureau hopes to determine the names of American Muslims who were recruited and sent to Afghanistan for training at bin Laden’s camps. “We don’t have a clue of all those who went through that system,” an FBI official said.