Trump on nuclear weapons tweet: 'Let it be an arms race'
Trump says US must 'expand its nuclear capability' until 'the world comes to its senses'
North Korea warns it would use nuclear weapons first if threatened
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North Korea conducts fifth and largest nuclear test
Trump reportedly asked adviser why US can't use nuclear weapons
Declassified photos show the US's final preparations for the only nuclear weapons attacks in history
Experts say Donald Trump's position on nuclear proliferation would be a disaster
North Korea fires short-range projectiles into sea amid tension over nuclear ambitions
Iran TV shows off allegedly downed Israeli drone
Investors Should Be Worried About Erratic North Korea
Trippy Game of the Day: Nuclearoids
For Obama, Nuclear Weapons Are a Last Resort
U.S. open to direct talks with North Korea