It is widely accepted that U.S. personnel have trained and funded groups in Iran in order to destabilize and overthrow the current regime under Mahmoud Ahmadinejad and that these groups used terroristic methods such as bombings and assassinations to destabilze the regime.
Fred Burton, former U.S. State Department counterterrorism agent, wrote:
Specifically, though, in this instance the blogger was referring to actions taken by Rudolph Giuliani, former Homeland Security Secretary Tom Ridge, former National Security Advisor Fran Townsend, and former Attorney General Michael Mukasey. The blogger’s volley is leveled at the men for not just for supporting terror but for committing a crime in doing so. The men are accused of aiding Mujaheddin-e Khalq (MEK).
MEK is a communist group that helped Saddam Hussein carry out attacks against Shiites in the '90s, attacked Americans in Iran in the '80s, and helped with the takeover of the U.S. embassy in Tehran in 1979. In 2009, it was designated by the United States to be a foreign terrorist organization.
But the United States has laws against advocating on behalf of any group lableled a "foreign terrorist organization" by the United States.
Georgetown University law professor and attorney David Cole had this to say in the January 3 New York Times:
The problem is that the United States government has labeled the Mujahedeen Khalq a 'foreign terrorist organization,' making it a crime to provide it, directly or indirectly, with any material support. It is therefore a felony, the government has argued, to file an amicus brief on behalf of a 'terrorist' group, to engage in public advocacy to challenge a group’s 'terrorist' designation or even to encourage peaceful avenues for redress of grievances.
The Supreme Court has ruled that any "advocacy performed in coordination with, or at the direction of, a foreign terrorist organization" is a crime. In addition, the Patriot Act makes it a crime to help any group designated as terrorist by the State Department.