PRISM was such a good data-mining system that it missed the one of the Boston bombers even when the US government was repeatedly warned, years ago:

Deceased Boston Marathon bombing suspect Tamerlan Tsarnaev came to the attention of the FBI on at least two occasions prior to a Russian government warning in March 2011 that said he appeared to be radicalizing, FBI Director Robert Mueller said in Congressional testimony this week.

The earlier references have led some lawmakers to question whether the FBI acted too quickly in closing an assessment of Tsarnaev’s potential ties to terrorism done in response to the Russian request.

In a little-noticed exchange before the House Judiciary Committee Thursday, Mueller acknowledged that the Russian alert was not the first time the elder Tsarnaev brother crossed the FBI’s radar.

“His name had come up in two other cases,” Mueller said in response to questions from Rep. Steve King (R-Iowa). “Those two other cases, the individuals had their cases closed. So, he was one or two person [sic] away.”

Non-existent enforcement of current laws and processes doesn’t constitute a need for data-mining the information of innocent citizens.

Steve King said his most urgent concern is that Chechens in the U.S. may be winning asylum without anyone in the U.S. government checking with Russia about whether the individuals have terrorist ties. “My concern is how many terrorists are coming into the United States and are receiving asylum?…What’s the total number of others who might have come in under that same window?” the congressman asked.

Another reason why the Gang of Eight’s shamnesty bill should be rejected.