Russia, especially those interested in testing this technology, is not an irrational claim. At least Russia has invested heavily in electronic warfare technology, which can "interfer" with a variety of signals, making it unusable. The US Army's Office of Foreign Military Research stated in a 2016 intelligence summary that Russia has integrated a large network of signal jammer into its civilian cell phone network, which could ignite GPS navigation to prevent smart missiles or other threats that rely on it.
