The standard argument for why Donald Trump is wrong when he says that he wants to shut down immigration from violence-plagued countries is that the U.S. government will “vet” potential immigrants and screen out those who are prone to waging jihad or likely to perpetrate other forms of violence.
I always wondered how this was going to work, especially since the people being screened would be coming from a culture in which neither speech nor documents are in the English language. Would it be the U.S. military, which failed to notice the sinking of the USS Indianapolis, for example? The FBI that failed to heed flight instructor warnings about the 9/11 hijackers? The FBI that, after being tipped off by the Russians (they were our friends back then, but we hate them now?) about the Tsarnaev family, investigated and cleared the Tsarnaev brothers?
Now we’ve got a new data point in that the FBI was tipped off to Nikolas Cruz’s likely behavior (Miami Herald) and yet failed to prevent the Stoneman Douglas High School shooting. The local police also got some tips. Compared to screening potential immigrants, this was an easy situation for law enforcement. The people offering the tips were native English speakers describing events that had occurred within the U.S. The potential criminal was a native English speaker. There was no need for an interpreter and no need to verify information about an event that had occurred on the other side of the planet.
Government does some great stuff (as you’d hope given $4 trillion per year in federal spending alone), but should we give up on the idea that government can usefully predict which people are most likely to commit violent acts?