Read why Ellis Talton and Remington Tonar say that lack of funding and expertise can threaten U.S. infrastructure from cyber attacks on Forbes :
As our physical infrastructure becomes increasingly digitalized, it also becomes increasingly vulnerable to cyber attack. Russian hackers, for example, have been trying to compromise U.S. electrical infrastructure for years, and successfully cut off power to hundreds of thousands of people throughout Ukraine in 2015 and again in 2016. Beyond our energy infrastructure, traffic signals are also susceptible to being hijacked, as numerous demonstrations have proven.
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