Zach Kessel writes for National Review Online about a damaging new claim from federal government whistleblowers.

John Kerry prevented the United States Department of Justice and Federal Bureau of Investigation from arresting Iranian terrorists on American soil while negotiating the Joint Comprehensive Plan of Action — the Iran nuclear deal — according to whistleblowers who provided information to Senators Chuck Grassley (R., Iowa) and Ron Johnson (R., Wis.).

“Unclassified and legally protected whistleblower disclosures provided to our offices show that while the Obama/Biden administration publicly committed to ‘prevent[ing]” Iran from acquiring nuclear weapons by raising the cost of Iran’s defiance of the international community,’ then-Secretary of State John Kerry actively interfered with the Federal Bureau of Investigation (FBI) executing arrest warrants on individuals in the U.S. illegally supporting Iranian efforts, including financial efforts, to develop weapons of mass destruction (WMD) and its ballistic missile program,” Grassley and Johnson wrote in a Tuesday letter to Secretary of State Antony Blinken. “The records show that Justice Department and FBI leadership, to include then-Attorney General Lynch and then-FBI Director Comey, failed to take the necessary steps to stop Kerry’s obstructive efforts against law enforcement.”

A 2015 email exchange between two FBI agents included in the letter shows one saying to the other that the agency would have to wait until the Obama administration concluded its negotiations with Iran to arrest Iranian actors operating within the U.S.

“We are all beside ourselves on asking the field to stand down on a layup arrest, however as it stands right now we all have to sit back and wait until the US and Iran negotiations resolve themselves,” one of the agents wrote. “We will continue to argue for aggressive action, however we will probably lose.”

Unclassified email records, according to the letter, “detailed at least eight instances connected to the Iran deal where the ‘FBI/DOJ/USG could have moved forward with these cases but the State Department chose to block them’” and that, “in six of these instances, the FBI lost the opportunity to arrest the main subject.”