Yes, Russia has the largest nuclear stockpile in the world, they absolutely work and it's unwise to base your opinions on their nuclear and tactical capabilities based on their slow advance into Ukraine.
The Poseidon is a 100 megaton nuclear torpedo.
It doesn't need to get anywhere near a carrier group to knock out the entire group. It is twice as powerful as the largest nuke ever detonated (at 57megatons) and a Russian sub can carry four of these torpedoes:
“All buildings in the village of Severny (both wooden and brick), located 55 km (34 mi) from ground zero within the Sukhoy Nos test range, were destroyed. In districts hundreds of kilometers from ground zero wooden houses were destroyed, stone ones lost their roofs, windows, doors, and radio communications were interrupted for almost one hour. One participant in the test saw a bright flash through dark goggles and felt the effects of a thermal pulse even at a distance of 270 kilometres (170 mi). The heat from the explosion could have caused third degree burns 100 km (62 mi) away from ground zero. A shock wave was observed in the air at Dikson settlement 700 km (430 mi) away; windowpanes were partially broken to distances of 900 kilometres (560 mi)."
I'm a tenth generation American. Pointing out facts is called being a realist. And I'm not impressed with a bunch of armchair generals that think that war with Russia would be easy because their Tik Tok feed told them so.
The Poseidon is a 100 megaton nuclear torpedo.
It doesn't need to get anywhere near a carrier group to knock out the entire group. It is twice as powerful as the largest nuke ever detonated (at 57megatons) and a Russian sub can carry four of these torpedoes:
“All buildings in the village of Severny (both wooden and brick), located 55 km (34 mi) from ground zero within the Sukhoy Nos test range, were destroyed. In districts hundreds of kilometers from ground zero wooden houses were destroyed, stone ones lost their roofs, windows, doors, and radio communications were interrupted for almost one hour. One participant in the test saw a bright flash through dark goggles and felt the effects of a thermal pulse even at a distance of 270 kilometres (170 mi). The heat from the explosion could have caused third degree burns 100 km (62 mi) away from ground zero. A shock wave was observed in the air at Dikson settlement 700 km (430 mi) away; windowpanes were partially broken to distances of 900 kilometres (560 mi)."
https://en.m.wikipedia.org/wiki/Tsar_Bomba