North Korea’s second strike capability
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North Korea may have fired another submarine-launched ballistic missile – a technology it had been developing before it halted all long-range missile testing and began talks with the U.S. in 2018
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Sinpo-class submarine

Length: 68m
Speed: 10 knots (dived est.) 
Propulsion: Diesel-electric
Crew: 30-50

Conning tower: Satellite imagery indicates submarine has one or two launch silos mounted in sail

Two or four torpedo tubes

1. Cold launch: Missile expelled from silo by compressed air
2. Solid fuel engine ignites above water

NK-11 (Polaris-1) Length: 9.3m

Warhead: 650kg
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Apr 2016: First submarine launch of KN-11 missile
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Jun 2018: First summit between Kim Jong-un and U.S. President Donald Trump in Singapore
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Feb 2019: Second meeting in Hanoi breaks down after North refuses nuclear disarmament
in return for lifting sanctions
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Jun: Trump and Kim meet for third time at Demilitarised Zone between two Koreas. Meeting followed by series of short-range launches over next months
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Oct: North Korea thought to have launched first undersea missile in three years
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Sources: Stratfor, The Diplomat, 38 North.org, H I Sutton Picture: KCNA © GRAPHIC NEWS