Can South Korea’s nuclear submarine dreams survive a Democrat-led US Congress?

South Korea is ramping up diplomatic efforts as fresh hurdles loom for its nuclear-powered submarine ambitions following a Democratic Party takeover of the US Congress.

Seoul’s Defence Acquisition Programme Administration last week approved preliminary plans for the submarines, with design work set to begin next year under an initial budget of 96.6 billion won (US$72.5 million) and delivery targeted for the late 2030s or beyond.

While US President Donald Trump endorsed the submarine plans at a...