Admiral Sir Tony Radakin, Chief of the British Defence Staff has told The Times that Russia is a major threat to the UK and its allies at sea. Russian submarines are very active and they could cut undersea cables in a war, which would severely damage the economies of the affected countries by severing their overseas communication links.
Radakin has, however, had a recent telephone call with General Valery Gerasimov, his Russian counterpart., the first such call since 2019.
In 1914, Britain cut Germany’s trans Atlantic cables, but cable communications were not then as vital to commerce as they now are.
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Radakin also warns of the threat from Russia’s 3,850 mph hypersonic missiles. It test fired 10 from a frigate and two from a submarine last month. China has also tested such missiles and North Korea claims to have done so.
In the early hours of 5 August 1914, only a few hours after war was declared, Britain carried out something that seemed to be minor, but was actually vital. A British cable ship severed five German overseas underwater cables, which passed from Emden through the English Channel to Vigo, Tenerife, the Azores and the USA
This cut direct German communications to outside Europe, most significantly to the United States. The British could now intercept German signals to their embassies. They were sent in code, but British codebreakers were eventually able to read them.
Most significantly, Britain intercepted the Zimmerman Telegram, sent to the German Ambassador to Mexico. If the USA went to war with Germany, he was to offer the Mexicans an alliance with the promise that they would receive Texas, New Mexico and Arizona. Its revelation helped to push the USA into war with Germany.