There are methods to test system vulnerability to EMPs without exploding nuclear weapons.

CENTERFORSECURITYPOLICY: Center For Security Policy

But anti-nuclear group Pawb says it has concerns about Wylfa's vulnerability to cyber-attacks and air assaults.

BBC: Wylfa and other UK nuclear stations in 'safe hands'

Until, that is, even he and the man who signed the treaty for the United States, Richard Nixon, publicly acknowledged in the 1990s that such deliberate vulnerability made no sense in the post-Cold War world with its proliferating missiles and nuclear programs.

CENTERFORSECURITYPOLICY: The Denuclearizers' Bridge-jump