The United States Air Force guards against electromagnetic pulse attacks. Do we have to worry?

A US air base in Texas has taken the first steps to protect itself against an electromagnetic pulse (EMP) attack. But what exactly is an EMP and how big is the threat?

Officials at the San Antonio Joint Base in Lackland, Texas, have requested bids to conduct an investigation at a facility called the Petroleum, Oil and Lubrication Complex. The investigation will identify any equipment that could be vulnerable to an EMP, ahead of more detailed vulnerability testing, according to the request. After that, officials would figure out ways to keep that equipment safe in the event of an EMP attack.

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