On September 11, President Joe Biden's administration executed a prisoner exchange agreement with Iran that was criticized as a bad deal at the time but has since been revealed to be even worse than initially imagined.

Not only did the terrorism-funding regime in Tehran gain access to $6 billion in frozen sanctioned funds, Iran also had several of its own prisoners in the U.S. released, including three who are U.S. citizens or permanent residents who will continue to pose a national security threat, National Review reported.

Given the citizenship and residency status of those three individuals, they can't be deported back to Iran and will instead remain in the U.S. with ostensibly cleared records and great incentive to continue doing the things that threaten U.S. national security and landed them in prison in the first place.

$6 billion in Iranian funds unfrozen

The most obvious and immediately recognized problem with the Sept. 11 prisoner swap with Iran was the unfreezing of $6 billion in sanctioned Iranian oil revenues held in South Korean banks and the subsequent transfer of those funds to a Qatari bank, purportedly with restrictions in place to ensure those funds are only used in the future for purely humanitarian purposes like food and medicine for the Iranian people.

In light of the near certainty that Iran backed and perhaps even helped plan Hamas' recent murderous incursion into Israel, which cost the lives of more than 1,200 mostly civilian Israelis and foreign citizens, many critics are now demanding that the $6 billion be refrozen and denied to Iran, including a group of Senate Republicans, according to The Hill.

"Your administration claims these funds are only available for humanitarian use, but money is fungible, and there is significant risk they could be used to further efforts by Iran or Hamas against Israel," the senators wrote. "Moreover, allowing $6 billion to flow into Iran’s economy, even if the purpose is for humanitarian aid, allows the Iranian regime to reallocate even more funds to supporting terrorism."

The released Iranian prisoners

National Review noted that the unfrozen $6 billion in Iranian funds was but one bad aspect of the terrible deal that was equaled or surpassed in that regard by the release of the Iranian prisoners, including the three who were "released to continue operating in the United States."

USA Today reported that months or even years and unquantifiable law enforcement resources were expended to investigate and prosecute the Iranian prisoners for various crimes that, while perhaps "non-violent," as the Biden administration chose to highlight, nonetheless threatened national security.

The two released prisoners who were sent back to Iran via Qatar are Mehrdad Ansari, who evaded sanctions to send sensitive dual-use parts and technology back to Iran that could be used in military and nuclear applications, and Reza Sarhangpour Kafrani, a Canadian-Iranian who unlawfully exported sensitive laboratory equipment useful for nuclear purposes to Iran.

Then there are the three prisoners who won't be going anywhere because they are citizens or permanent residents, including Amin Hasanzadeh, a former member of the Iranian military accused of illegally sending secret sensitive aerospace engineering documents to his brother in the Iranian military.

That also includes Kambiz Attar Kashani, a dual-citizen convicted for providing Iran with sensitive international banking information that will help them evade sanctions, and Kaveh Lotfolah Afrasiabi, a permanent resident charged with acting for years as an unregistered paid lobbyist and propagandist for Iran in violation of the Foreign Agents Registration Act.

Steep price paid could backfire on Biden

National Review noted that those three individuals with suddenly clean records could easily return to their prior criminal behaviors that undermine U.S. national security, and though the Biden administration has suggested the executive clemency they received could be revoked if they get in trouble again, that isn't really how that works and is also beside the point.

In his haste to appease Iran in order to secure the release of five American citizens the regime was holding -- don't forget also Biden's incessant efforts to revive the horrible 2015 Iran nuclear deal -- the president was willing to release five known national security threats and $6 billion to a nation that proudly funds and supports terrorism and violence against American interests and allies.

To be sure, getting the five captive Americans released is undeniably a good thing, but the already high cost paid -- which could soar even higher in the future if/when U.S. blood is spilled by Iran -- will likely forever be a likely avoidable stain on Biden's already otherwise poor record and reputation.