With the continuing escalation of rhetoric on terrorism and the most recent horror in Belgium, I wanted to suggest a common-sense, low cost approach to reducing attacks on the United States — reintroduce visa requirements for anyone wanting to enter the U.S. Legal residents and citizens would be the only exceptions.

When I was much younger, visas were required almost everywhere. With modern technology, costs would be minimal and allow advance screening of potential entrants (say one week minimum visa application prior to being allowed entry).

With “big data” technologies available to agencies such as the National Security Agency and Department of Homeland Security, background checking is fast and cheap. Doing this for everyone would remove any stigma, such as the Islamaphobia promulgated by some. Also pattern matching and machine learning could allow visa applicant relationships to be established and provide a very potent intelligence tool.

Jarmo Paukkunen

Bellevue