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North Korea has long boasted about its ability to bring down the United State’s financial systems and transport networks with a series of EMP attacks. Politicians in the US are said to be alarmed by the growing threat of a high-altitude nuclear blast and the resulting electromagnetic pulse. An EMP attack would fry the circuitry of mobile phones and wipe out online banking, food resources and the USA’s financial systems, resulting in a global financial crash, claimed Simpson. The blast of electromagnetic energy also has the ability to take down aeroplanes in flight and cause trains to stop in their tracks.

GETTY North Korea news: Kim Jong-un EMP attack could devastate the US economy

The whole world would suffer if there was a major breakdown of the United States John Simpson

Speaking to BBC’s Radio 5 Live, Simpson said: “One of the things that the North Koreans have been boasting about an electromagnetic pulse (EMP), which means firing a nuclear weapon up into the atmosphere and devastating the electrical grid of a country and all of its infrastructure. “If something like that were to happen, I don’t think it is at all likely, but when North Korea is boasting about it, then, of course, the whole world would suffer if there was a major breakdown of the United States, China or somewhere else – that would be absolutely devastating to the world economy. “There are serious dangers to the world economy, and I think this is why the Chinese are showing such signs of nervousness at the moment because they think that the world economy could be devastated if anything goes wrong at all.” North Korea has previously claimed it had two satellites in an “ideal altitude” to launch such an attack against the USA.

Amid fears of an impending attack from North Korea’s despot leader Kim Jong-un, Donald Trump has refused to rule out military action against the rogue state. The US Presdient left all options on the table when he was asked if he would react with military force to North Korea’s latest weapons test, telling reporters: “We’ll see.” However, his Secretary of Defence, General James Mattis was more direct in his threats of military action as he refused to rule out a devastating end to the Kim regime through the USA’s “many military options”. General Mattis said: “Our commitment among the allies are ironclad. Any threat to the United States or its territories, including Guam, or our allies will be met with a massive military response, a response both effective and overwhelming.

GETTY North Korea has carried out a series of missile tests amid World War 3 fears

“We are not looking to the total annihilation of a country, namely North Korea, but as I said we have many options to do so.” The USA has assembled an impressive arsenal, which includes a sophisticated anti-missile system, as it looks to intimidate the Kim regime. The Terminal High-Altitude Area Defence (THAAD) system, despite criticism from Pyongyang, is ready and waiting to intercept missiles and destroy incoming projectiles while they are in mid-flight. South Korea’s Government has released details, revealing it will roll out four more US-designed THAAD systems after the Kim regime’s latest nuclear test.

North Korea conducts 'perfect' hydrogen bomb test Sun, September 3, 2017 North Korea conducted its sixth and most powerful nuclear test, which it said was a successful detonation of an advanced hydrogen bomb Play slideshow REUTERS 1 of 9 North Korean leader Kim Jong Un provides guidance on a nuclear weapons program in this undated photo released by North Korea's Korean Central News Agency