Anti-nuclear campaigners expressed alarm Thursday as the Federation of American Scientists revealed the U.S. has for the first time deployed a \u0022low-yield\u0022 nuclear warhead on a submarine that is currently patrolling the Atlantic Ocean.The USS Tennessee left a port in Georgia last month, and Hans Kristenson of FAS said Wednesday that the submarine is the first U.S. ship to patrol with the W76-2 on board—an occurrence which arms control groups says will make nuclear war more likely.Tim Wright, treaty coordinator for the International Campaign to Abolish Nuclear Weapons (ICAN), called the news \u0022an alarming development that heightens the risk of nuclear war.\u0022An alarming development that heightens the risk of nuclear war. The United States\u0026#039; new \u0022low-yield\u0022 nuclear warheads are still powerful enough to kill many tens of thousands of people. #nuclearban https://t.co/OGtKrVwQUe— Tim Wright (@TimMilesWright) January 30, 2020The ready availability of the warhead on a military ship could cause a shift in thinking about nuclear weapons, with the government treating a nuclear launch as a way to fight wars rather than as a deterrent, nuclear critics say.The low-yield Trident nuclear warhead was commissioned in 2018 by President Donald Trump.The warhead has an explosive yield of five kilotons, about a third of the power of the atomic bomb dropped on Hiroshima, Japan in 1945, which killed 80,000 people instantly and tens of thousands later from radiation exposure.Compared to the bombings of Hiroshima and Nagasaki at the end of World War II, the effect of the W76-2 \u0022would be very beneficial to a military officer who was going to advise to the president whether we should cross the nuclear threshold,\u0022 according to Hans Kristensen, director of the Nuclear Information Project at FAS, which learned about the recent deployment from government briefings.The deployment of the W76-2 came five months after the president exited the Intermediate-Range Nuclear Forces (INF) Treaty, which the U.S. and Russia forged in 1987. The withdrawal from the treaty would \u0022put the world at heightened risk of nuclear weapons use and war,\u0022 ICAN said at the time.According to Trump\u0026#039;s Nuclear Posture Review (NPR), the U.S. government claims the Trident is a deterrent against Russia. As Kristensen wrote in Forbes last year, however, the Russian threat may be exaggerated by the Pentagon.\u0022It seems like a perfect threat-funding-loop sales pitch: Russia is increasing its non-strategic nuclear weapons that it is more prepared to use first, so give us more money to build new nukes,\u0022 wrote Kristensen. \u0022But...in stark contrast with the NPR claim, I hear there\u0026#039;s no significant increase in the total numbers. On the contrary, there has been a significant reduction over the past ten years—the very period the NPR uses as the basis for its threat assessment.\u0022While Russia\u0026#039;s nuclear threat level is questionable, Trump has said he may direct the use of nuclear weapons to respond to \u0022significant non-nuclear strategic attacks\u0022 on the U.S., its allies, or \u0022infrastructure.\u0022On social media, international anti-nuclear groups expressed alarm over the deployment of the Trident warhead.\u0022Usable\u0022 nukes bring us closer to the threshold of nuclear war. https://t.co/729C0Nviok— Scrap Trident (@ScrapTrident) January 29, 2020The presence of the warhead on a patrolling submarine \u0022brings us closer to the threshold of nuclear war,\u0022 tweeted the Scottish anti-nuclear campaign Scrap Trident.