Secret US Policy Blocks Agents From Looking at Social Media of Visa Applicants, Former Official Says State Department says lessons will be learned after California massacre.

 -- The State Department today said that “obviously things went wrong” in the visa background check for one of the San Bernardino shooters -- comments that came in the wake of an ABC News report that said officials by policy generally do not check social media postings of applicants due to civil liberties concerns and therefore would not have seen purported evidence of Tashfeen Malik’s radicalization online.

“It’s difficult to say exactly what [went wrong] and how, but for an individual to be able to come into this country – one who the FBI has maintained had terrorist tendencies or affiliations or sympathies at least for a couple years, and then to propagate an attack like that on our own soil, obviously, I think it’s safe to say there’s going to be lessons learned here,” State Department spokesperson John Kirby told reporters.

Fearing a civil liberties backlash and "bad public relations" for the Obama administration, Homeland Security Secretary Jeh Johnson refused in early 2014 to end the secret U.S. policy that prohibited immigration officials from reviewing the social media messages of all foreign citizens applying for U.S. visas, according to a former senior department official.

"During that time period immigration officials were not allowed to use or review social media as part of the screening process," John Cohen, a former acting under-secretary at DHS for intelligence and analysis. Cohen is now a national security consultant for ABC News.

One current and one former senior counter-terrorism official confirmed Cohen's account about the refusal of DHS to change its policy about the public social media posts of all foreign applicants.

A spokesperson for the DHS, Marsha Catron, told ABC News that months after Cohen left, in the fall of 2014, the Department began three pilot programs to include social media in vetting, but current officials say that it is still not a widespread policy. A review of the broader policy is already underway, the DHS said.

The revelation comes as members of Congress question why U.S. officials failed to review the social media posts of San Bernardino terrorist Tashfeen Malik. She received a U.S. visa in May 2014, despite what the FBI said were extensive social media messages about jihad and martyrdom.

Sen. Charles Schumer, D-N.Y., demanded Sunday that the U.S. immediately initiate a program that would check the social media sites of those admitted on visas."

"Had they checked out Tashfeen Malik," the senator said, "maybe those people in San Bernardino would be alive."

Former DHS under-secretary Cohen said he and others pressed hard for just such a policy change in 2014 that would allow a review of publicly-posted social media messages as terror group followers increasingly used Twitter and Facebook to show their allegiance to a variety of jihadist groups.

Cohen said officials from United States Citizenship and Immigration Services (USCIS) and U.S. Immigration and Customs Enforcement (ICE) both pressed for a change in policy.

"Immigration, security, law enforcement officials recognized at the time that it was important to more extensively review public social media postings because they offered potential insights into whether somebody was an extremist or potentially connected to a terrorist organization or a supporter of the movement," said Cohen, who left DHS in June 2014.

Cohen said the issue reached a head at a heated 2014 meeting chaired by Homeland Security Deputy Secretary Alejandro Mayorkas, other top deputies and representatives of the DHS Office of Civil Liberties and the Office of Privacy.

"The primary concern was that it would be viewed negatively if it was disclosed publicly and there were concerns that it would be embarrassing," Cohen said in an interview broadcast on "Good Morning America" today.

Cohen said he and others were deeply disappointed that the senior leadership would not approve a review of what were publicly-posted online messages.

"There is no excuse for not using every resource at our disposal to fully vet individuals before they come to the United States," Cohen said.

A former senior counter-terrorism official, who participated in the 2014 discussion, said, "Why the State Department and Homeland Security Department have not leveraged the power of social media is beyond me."

"They felt looking at public postings [of foreign U.S. visa applicants] was an invasion of their privacy," the official told ABC News. "The arguments being made were, and are still, in bad faith."

Cohen said the disclosures by Edward Snowden about National Security Agency (NSA) surveillance policies fed concern of bad public relations that would affect the U.S. government's standing with civil rights groups and European allies.

"It was primarily a question of optics," said Cohen. "There were concerns from a privacy and civil liberties perspective that while this was not illegal, that it would be viewed negatively if it was disclosed publicly."

Cohen said he and others were deeply troubled by the decision.

"If we don't look and don't review, we don't know," he said.

Officials said that because Malik used a pseudonym in her online messages, it is not clear that her support for terror groups would have become known even if the U.S. conducted a full review of her online traffic.

DHS's Catron told ABC News the Department is "actively considering additional ways to incorporate the use of social media review in its various vetting programs," while keeping an eye on privacy concerns.

"The Department will continue to ensure that any use of social media in its vetting program is consistent with current law and appropriately takes into account civil rights and civil liberties and privacy protections," Catron said.

State Department records show that in 2014 the U.S. government issued nearly 10 million nonimmigrant visas, over 40,000 of which were K-1 fiancé visas like the one Malik used to enter the country.