Could the Ukraine war devolve into an  

EMP apocalypse for America?

...a missile-delivered electromagnetic pulse (EMP) of sufficient size, exploded high above St. Louis, for example, could basically fry the electricity systems of the United States and those of the main populated parts of Canada and northern Mexico.

Imagine most of the United States with no electricity, no ATMs, few working vehicles, few functioning hospitals, no delivery of prescription medicines, or food or fresh water or sewage treatment. Most of the U.S. population could be reduced to a lifestyle like that of the 1800s. EMP Commission estimates project a death toll of 90 percent of the population within one year, were something of this nature to happen. Remaining authorities would be overwhelmed by civil unrest decimating the dwindling population as they fought for their survival.

...

The question, then, is: “Would such an EMP attack provoke a nuclear response by the United States?”...

...if...it was clear from missile tracks that Russia did, the American response likely would be based on 30-year-old nuclear intercontinental ballistic missiles (ICBMs) and submarine-launched ballistic missiles (SLBMs) targeted toward Russia. U.S. missiles would be met with batteries of highly capable Russian anti-missile S300s, S400s and S500s.

Russia recently demonstrated that its S550 anti-satellite missiles can destroy American military satellites, which would then degrade U.S. command-control-communications and GPS coordination of the targeting mechanisms in U.S. missiles. Consequently, U.S. missiles might be rerouted — who knows where — or more easily destroyed by Russia’s anti-missile defenses. 

Of course, if the United States were to launch ICBMs against Russia, unquestionably Moscow would respond in kind. If they did, an already EMP-devastated U.S. could be utterly destroyed.

###

the employment of an EMP weapon against a country is the scenario of war most likely to collapse the functionality of the electrical network of the country.^[2]