Russian Submarine in Cuba: Why The West Fears Russia's Yasen Class N-Sub?

Russia’s nuclear-powered submarine is now deployed in American waters. The Kazan 561 or K-561 is an advanced Russian Yasen Class nuclear-powered cruise missile submarines. Operated only by Russia, Yasen class submarines are the newest subs in the Russian navy and are known for their sophisticated design, armament, and stealth capabilities. Is its deployment bringing US and Russia to the brink of war.