Russia in particular has grabbed headlines with renewed submarine activity in the Atlantic.
Russia has added over a dozen new submarines to its ranks since annexing Crimea.
India has equipped its INS Arihant nuclear submarine with K-15 Sagarika missiles capable of hitting targets 435 miles away.
"There is no doubt that he murdered Kim Wall on purpose and that he had a sexual motive," said the prosecutor.
The video shows what's happening both outdoors and inside the submarine, too.
Naples Mayor Luigi de Magistris said his "City of Peace" was no place for nuclear weapons or nuclear-powered vessels.
A Danish Navy officer says it can't have happened the way Madsen says.
In 2017, Russia's warships spent four times longer on deployment and drills in the Pacific Oceans than they were planning to.
The game pads are around 1,000 times cheaper and require less training since most young sailors have played on an Xbox before.
He said the subs got close to an American military base but nobody knew they were there.
The Columbia-class nuclear submarine fleet will enter service in 2031 and serve until 2085.
The system could turn into a "runaway submarine with enough nuclear arsenals to destroy a continent," says researcher Zhu Min.
After passing its testing, the Sea Hunter has been given to the Navy's research office who will develop it into a ship fit for the ranks of a fleet.
A charge sheet alleged that Wall's murder had been premeditated because Madsen brought "tools" he normally did not take on submarine trips.
The INS Arihant is grounded and has been undergoing repairs for the past ten months after a "human error" caused major damages to it's propulsion chamber.
North Korea analysts said the next threat could come from underwater.
The alliance is concerned about Moscow's presence near undersea communication lines.
The 44-crew sub has been missing for over a week, and oxygen supplies may be running out.
The Knyaz Vladimir is the first of five nuclear-powered submarines that Moscow believes will upgrade its navy.
Is this the beginning of the end for the South China Sea conflict?
"I am not a woman, so I don't have bad days," the Russian leader said in an interview.
"We have a lot of firepower over there," Trump said to Duterte, before revealing that firepower included two nuclear submarines.
The Vladimir Monomakh will be permanently deployed in Russia's far east.
U.K. cabinet minister in charge of Brexit made arguments that contradict the government he has since joined.