One of the rampage killers in the recent mass-shooting in San Bernardino, California entered on the K‑1 visa for fiancés with the intent of marrying her fellow shooter Syed Farook – an American citizen. From 1989 to 2014, the government issued 512,164 K‑1 visas. According to David North of the restrictionist Center for Immigration Studies (CIS), this is the first potential terrorist to enter the United States on a K‑1 visa.
One potential terrorist out of 512,164 K‑1 visas issued is not a good reason to tighten that visa’s already rigorous application process.
In 2015 there have been four mass shooting according to Mother Jones with 37 fatalities and 33 injuries. Your chance of being killed in a mass shooting in the United States in 2015 is one in 8,617,758. Your chance of chance of being injured in a mass shooting this year so far is one in 9,662,335. Your chance of being killed or injured in a mass shooting is one in 4,555,101.
Your chance of being killed by a foreign-born terrorist in 2015 (so far) is one in 16,781,950, your chance of being wounded is one in 13,863,350, and your chance of being killed or wounded is one in 7,591,835, assuming the broadest possible definition of terrorism committed by an immigrant (Dylan Roof is was born in the United States) on U.S. soil.